ci: adopt pnpm/action-setup for symmetric pnpm store caching

Convert the hand-rolled corepack + store-path + actions/cache pnpm setups
to pnpm/action-setup@v4 + setup-node cache: pnpm (the landlock-run.yml
pattern) in e2e.yml, docs-pages.yml, pi-ai-provider-e2e.yml,
build-exe-for-python-sdk.yml, and ci.yml's node-compat and benchmark
jobs. The enterprise restore-only PR jobs and the Windows job keep their
documented asymmetries; serial-linux keeps its hand-rolled store cache
because it produces the exact key those restore-only jobs consume, and
only swaps corepack for the action.

Implements and moves the CI-caching Agent Note from PR #667 to
implemented/, recording the serial-linux producer exception and the
exact-key (no restore-keys prefix) behavior of setup-node's cache.

.agents/notes/implemented/process/2026-07-26-pnpm-action-setup-for-symmetric-ci-caching.i18n.yaml

@@ -2,5 +2,5 @@
 # side as of the last confirmed-consistent state. Both languages carry equal authority;
 # after editing either side, bring the other along and re-record with:
 #   pnpm run verify-translation-pairing --write
-2026-07-26-pnpm-action-setup-for-symmetric-ci-caching.md: 63e3f45ab2340ee2b732da286117e25be45bed08
-2026-07-26-pnpm-action-setup-for-symmetric-ci-caching.zh.md: 2348e07d58f7f0ed39a1759cc30133c8e15dbc4a
+2026-07-26-pnpm-action-setup-for-symmetric-ci-caching.md: 0cc0a09dfe1019d80b08599a245ce4bb044d81c5
+2026-07-26-pnpm-action-setup-for-symmetric-ci-caching.zh.md: 477f8eed61579eb9c4f18701a39307daf098407d

.agents/notes/implemented/process/2026-07-26-pnpm-action-setup-for-symmetric-ci-caching.md

@@ -0,0 +1,32 @@
+# Agent Note: Use pnpm/action-setup for symmetric CI pnpm caching
+
+Status: implemented
+
+English | [中文](2026-07-26-pnpm-action-setup-for-symmetric-ci-caching.zh.md)
+
+## Problem
+
+Five workflows repeated a hand-rolled three-step pnpm setup — `corepack enable`, `pnpm store path --silent >> $GITHUB_OUTPUT`, then `actions/cache@v4` keyed on `pnpm-lock.yaml`: `e2e.yml`, `docs-pages.yml`, `pi-ai-provider-e2e.yml`, `build-exe-for-python-sdk.yml`, and the node-compat, serial-linux, and benchmark jobs of `ci.yml` (~40–60 YAML lines total). The maintained equivalent — `pnpm/action-setup@v4` (reads `packageManager` from package.json) plus `actions/setup-node` with `cache: pnpm` — was already proven in-repo in `landlock-run.yml`, and also insulates against corepack's removal from newer Node distributions.
+
+## Decision
+
+The symmetric-cache setups use `pnpm/action-setup@v4` followed by `actions/setup-node` with `cache: pnpm`, the `landlock-run.yml` pattern: `e2e.yml`, `docs-pages.yml`, `pi-ai-provider-e2e.yml`, `build-exe-for-python-sdk.yml`, and the node-compat and two benchmark jobs of `ci.yml`. The larger-runner benchmark keeps its store cache Linux-only through a conditional `cache:` input, mirroring the required Windows job's deliberate skip; the consolidated benchmark caches on both platforms as before.
+
+Explicitly NOT converted:
+
+- the three enterprise-runner PR jobs in `ci.yml` — they deliberately use `actions/cache/restore` only, keeping cache compression/upload off the paid latency-critical path, an asymmetry `setup-node`'s cache cannot express;
+- the Windows job, which deliberately skips the store cache;
+- the store-cache step of `ci.yml`'s serial-linux job — the job swaps `corepack enable` for `pnpm/action-setup@v4`, but its `pnpm store path` + `actions/cache@v4` steps stay hand-rolled because the master-push serial-linux run is the save side that populates the exact key and path the enterprise restore-only jobs consume; converting the producer to `setup-node`'s own key format would silently starve their restores.
+
+## Alternatives considered
+
+- **Keep the hand-rolled steps.** They work, but they are five drifting copies of setup boilerplate, and the corepack dependency is a known future break.
+- **Convert everything including the enterprise jobs.** Rejected: the restore-only asymmetry is a documented latency decision in `ci.yml`'s comments; erasing it to unify tooling inverts the priority.
+- **Convert serial-linux's store cache too.** Rejected during implementation: the proposal counted serial-linux among the symmetric setups, but its cache step is the producer half of the enterprise jobs' restore-only pairing — moving it to `setup-node`'s key format is the enterprise conversion by another route.
+
+## Consequences
+
+- The corepack dependency is gone from every converted workflow; pnpm arrives via the pnpm team's official action, already trusted in-repo (`landlock-run.yml`).
+- The cache-key format changed once; one cold run per converted lane repopulates it, after which hit rates match the old steps. The built-in key spans platform, arch, and the lockfile hash but not the Node version, so the node-compat matrix legs share one store entry — safe, because the pnpm store is Node-version-independent.
+- `setup-node`'s built-in pnpm cache restores by exact key only, with no `restore-keys` prefix fallback: a `pnpm-lock.yaml` change starts a converted lane from a cold store instead of seeding from the previous entry.
+- About 75 net lines of workflow YAML removed; the enterprise-runner PR jobs and the Windows job are byte-identical, and serial-linux keeps producing the key they restore.

.agents/notes/implemented/process/2026-07-26-pnpm-action-setup-for-symmetric-ci-caching.zh.md

@@ -0,0 +1,32 @@
+# Agent Note: 用 pnpm/action-setup 实现对称的 CI pnpm 缓存
+
+Status: implemented
+
+[English](2026-07-26-pnpm-action-setup-for-symmetric-ci-caching.md) | 中文
+
+## 问题
+
+五个工作流曾重复着同一套手写（hand-rolled）的三步 pnpm 设置——`corepack enable`、`pnpm store path --silent >> $GITHUB_OUTPUT`、再加以 `pnpm-lock.yaml` 为缓存键的 `actions/cache@v4`：`e2e.yml`、`docs-pages.yml`、`pi-ai-provider-e2e.yml`、`build-exe-for-python-sdk.yml`，以及 `ci.yml` 的 node-compat、serial-linux 与 benchmark 作业（合计约 40–60 行 YAML）。与之等价、由官方维护的做法——`pnpm/action-setup@v4`（从 package.json 读取 `packageManager`）加带 `cache: pnpm` 的 `actions/setup-node`——当时已在仓库内的 `landlock-run.yml` 中得到验证，同时还能隔绝 corepack 被从较新 Node 发行版中移除的影响。
+
+## 决策
+
+各对称缓存设置现采用 `pnpm/action-setup@v4` 后接带 `cache: pnpm` 的 `actions/setup-node`，即 `landlock-run.yml` 的模式：`e2e.yml`、`docs-pages.yml`、`pi-ai-provider-e2e.yml`、`build-exe-for-python-sdk.yml`，以及 `ci.yml` 的 node-compat 与两个 benchmark 作业。larger-runner benchmark 通过条件化的 `cache:` 输入让 store 缓存仅限 Linux，与必需 Windows 作业刻意跳过缓存的做法保持一致；consolidated benchmark 与之前一样在两个平台上都启用缓存。
+
+以下明确未做转换：
+
+- `ci.yml` 中运行在企业 runner 上的三个 PR（Pull Request）作业——它们刻意只用 `actions/cache/restore`，把缓存压缩/上传挡在付费且延迟敏感的关键路径之外，这种不对称是 `setup-node` 的缓存无法表达的；
+- Windows 作业，它刻意跳过 store 缓存；
+- `ci.yml` 中 serial-linux 作业的 store 缓存步骤——该作业把 `corepack enable` 换成了 `pnpm/action-setup@v4`，但其 `pnpm store path` + `actions/cache@v4` 步骤仍保持手写，因为 master 推送触发的 serial-linux 运行正是写入侧，负责填充企业只恢复不上传（restore-only）作业所消费的那个精确缓存键与路径；把生产者改成 `setup-node` 自有的键格式，会悄然断供它们的恢复。
+
+## 曾考虑的替代方案
+
+- **保留手写步骤。** 它们能用，但那是五份会各自漂移的设置样板副本，而且对 corepack 的依赖是已知的未来失效点。
+- **连企业作业在内全部转换。** 否决：只恢复不上传的不对称是 `ci.yml` 注释中有记录的延迟决策；为统一工具而抹掉它，属于颠倒优先级。
+- **连 serial-linux 的 store 缓存也转换。** 实现期间否决：提案曾把 serial-linux 计入对称设置，但其缓存步骤是企业作业只恢复不上传配对中的生产者一半——把它改成 `setup-node` 的键格式，等于换条路径做了企业作业的转换。
+
+## 后果
+
+- 每个已转换的工作流都不再依赖 corepack；pnpm 经由 pnpm 团队的官方 action 提供，该 action 已在仓库内获得信任（`landlock-run.yml`）。
+- 缓存键格式变更了一次；每条已转换泳道各跑一次冷运行以重建缓存，此后命中率与旧步骤持平。内建缓存键涵盖平台、架构与锁文件哈希，但不含 Node 版本，因此 node-compat 矩阵的各条腿共享同一条 store 缓存记录——这是安全的，因为 pnpm store 与 Node 版本无关。
+- `setup-node` 内建的 pnpm 缓存只按精确键恢复，没有 `restore-keys` 前缀回退：`pnpm-lock.yaml` 一旦变更，已转换泳道会从冷 store 起步，而不是从上一条缓存记录播种。
+- 净删除约 75 行工作流 YAML；企业 runner 上的 PR 作业与 Windows 作业逐字节未动，serial-linux 继续生产它们所恢复的缓存键。

.agents/notes/proposed/process/2026-07-26-pnpm-action-setup-for-symmetric-ci-caching.md

@@ -1,31 +0,0 @@
-# Agent Note: Use pnpm/action-setup for symmetric CI pnpm caching
-
-Status: proposed
-
-English | [中文](2026-07-26-pnpm-action-setup-for-symmetric-ci-caching.zh.md)
-
-## Problem
-
-Five workflows repeat a hand-rolled three-step pnpm setup — `corepack enable`, `pnpm store path --silent >> $GITHUB_OUTPUT`, then `actions/cache@v4` keyed on `pnpm-lock.yaml`: `e2e.yml`, `docs-pages.yml`, `pi-ai-provider-e2e.yml`, `build-exe-for-python-sdk.yml`, and the node-compat, serial-linux, and benchmark jobs of `ci.yml` (~40–60 YAML lines total). The maintained equivalent — `pnpm/action-setup@v4` (reads `packageManager` from package.json) plus `actions/setup-node` with `cache: pnpm` — is already proven in-repo in `landlock-run.yml`, and also insulates against corepack's removal from newer Node distributions.
-
-## Proposal
-
-Convert the symmetric-cache workflows to `pnpm/action-setup@v4` + `setup-node` `cache: pnpm`. Explicitly do NOT convert:
-
-- the three enterprise-runner PR jobs in `ci.yml` — they deliberately use `actions/cache/restore` only, keeping cache compression/upload off the paid latency-critical path, an asymmetry `setup-node`'s cache cannot express;
-- the Windows job, which deliberately skips the store cache.
-
-## Alternatives considered
-
-- **Keep the hand-rolled steps.** They work, but they are five drifting copies of setup boilerplate, and the corepack dependency is a known future break.
-- **Convert everything including the enterprise jobs.** Rejected: the restore-only asymmetry is a documented latency decision in `ci.yml`'s comments; erasing it to unify tooling inverts the priority.
-
-## Acceptance criteria
-
-- The five symmetric workflows set up pnpm via the actions; one cold run per lane repopulates the new cache-key format, after which cache hit rates match the old steps.
-- The enterprise-runner PR jobs and the Windows job are untouched.
-
-## Risks
-
-- Cache-key format changes once (one cold run per lane).
-- A third-party action in more workflows; it is already trusted in-repo (`landlock-run.yml`) and is the pnpm team's official action.

.agents/notes/proposed/process/2026-07-26-pnpm-action-setup-for-symmetric-ci-caching.zh.md

@@ -1,31 +0,0 @@
-# Agent Note: 用 pnpm/action-setup 实现对称的 CI pnpm 缓存
-
-Status: proposed
-
-[English](2026-07-26-pnpm-action-setup-for-symmetric-ci-caching.md) | 中文
-
-## 问题
-
-五个工作流重复着同一套手写（hand-rolled）的三步 pnpm 设置——`corepack enable`、`pnpm store path --silent >> $GITHUB_OUTPUT`、再加以 `pnpm-lock.yaml` 为缓存键的 `actions/cache@v4`：`e2e.yml`、`docs-pages.yml`、`pi-ai-provider-e2e.yml`、`build-exe-for-python-sdk.yml`，以及 `ci.yml` 的 node-compat、serial-linux 与 benchmark 作业（合计约 40–60 行 YAML）。与之等价、由官方维护的做法——`pnpm/action-setup@v4`（从 package.json 读取 `packageManager`）加带 `cache: pnpm` 的 `actions/setup-node`——已在仓库内的 `landlock-run.yml` 中得到验证，同时还能隔绝 corepack 被从较新 Node 发行版中移除的影响。
-
-## 提案
-
-将各对称缓存工作流改为 `pnpm/action-setup@v4` + `setup-node` `cache: pnpm`。以下明确不做转换：
-
-- `ci.yml` 中运行在企业 runner 上的三个 PR（Pull Request）作业——它们刻意只用 `actions/cache/restore`，把缓存压缩/上传挡在付费且延迟敏感的关键路径之外，这种不对称是 `setup-node` 的缓存无法表达的；
-- Windows 作业，它刻意跳过 store 缓存。
-
-## 曾考虑的替代方案
-
-- **保留手写步骤。** 它们能用，但那是五份会各自漂移的设置样板副本，而且对 corepack 的依赖是已知的未来失效点。
-- **连企业作业在内全部转换。** 否决：只恢复不上传（restore-only）的不对称是 `ci.yml` 注释中有记录的延迟决策；为统一工具而抹掉它，属于颠倒优先级。
-
-## 验收标准
-
-- 五个对称工作流经由上述 action 完成 pnpm 设置；每条泳道各跑一次冷运行以重建新的缓存键格式，此后缓存命中率与旧步骤持平。
-- 企业 runner 上的 PR 作业与 Windows 作业保持原样不动。
-
-## 风险
-
-- 缓存键格式变更一次（每条泳道各一次冷运行）。
-- 更多工作流引入一个第三方 action；它已在仓库内获得信任（`landlock-run.yml`），且是 pnpm 团队的官方 action。

.github/workflows/build-exe-for-python-sdk.yml

@@ -124,9 +124,14 @@ jobs:
     steps:
       - uses: actions/checkout@v6
 
+      - uses: pnpm/action-setup@v4
+
+      # setup-node's built-in pnpm store cache keys on platform AND arch, so
+      # the Linux architectures sharing runner.os stay on separate caches.
       - uses: actions/setup-node@v6
         with:
           node-version: 24
+          cache: pnpm
 
       - uses: actions/setup-python@v6
         with:
@@ -135,21 +140,6 @@ jobs:
       - name: Install Python build tooling
         run: python -m pip install uv==0.11.23
 
-      - name: Enable corepack (pnpm)
-        run: corepack enable
-
-      - name: Resolve pnpm store path
-        id: pnpm-store
-        run: echo "path=$(pnpm store path --silent)" >> "$GITHUB_OUTPUT"
-
-      # Linux architectures share runner.os, so the cache key includes arch.
-      - uses: actions/cache@v4
-        with:
-          path: ${{ steps.pnpm-store.outputs.path }}
-          key: ${{ runner.os }}-${{ runner.arch }}-node-24-pnpm-${{ hashFiles('pnpm-lock.yaml') }}
-          restore-keys: |
-            ${{ runner.os }}-${{ runner.arch }}-node-24-pnpm-
-
       # Cache pkg's target Node binary; lockfile changes roll the
       # exact key while the restore prefix can seed its replacement.
       - uses: actions/cache@v4

.github/workflows/ci.yml

@@ -236,22 +236,12 @@ jobs:
     steps:
       - uses: actions/checkout@v6
 
+      - uses: pnpm/action-setup@v4
+
       - uses: actions/setup-node@v6
         with:
           node-version: ${{ matrix.node }}
-
-      - name: Enable corepack and resolve pnpm store path
-        id: pnpm-store
-        run: |
-          corepack enable
-          echo "path=$(pnpm store path --silent)" >> "$GITHUB_OUTPUT"
-
-      - uses: actions/cache@v4
-        with:
-          path: ${{ steps.pnpm-store.outputs.path }}
-          key: ${{ runner.os }}-node-${{ matrix.node }}-pnpm-${{ hashFiles('pnpm-lock.yaml') }}
-          restore-keys: |
-            ${{ runner.os }}-node-${{ matrix.node }}-pnpm-
+          cache: pnpm
 
       - name: Install (immutable)
         run: pnpm install --frozen-lockfile
@@ -324,17 +314,22 @@ jobs:
     steps:
       - uses: actions/checkout@v6
 
+      - uses: pnpm/action-setup@v4
+
       - uses: actions/setup-node@v6
         with:
           node-version: ${{ env.PRIMARY_NODE_VERSION }}
 
-      - name: Enable corepack and resolve pnpm store path
+      - name: Resolve pnpm store path
         id: pnpm-store
-        run: |
-          corepack enable
-          echo "path=$(pnpm store path --silent)" >> "$GITHUB_OUTPUT"
+        run: echo "path=$(pnpm store path --silent)" >> "$GITHUB_OUTPUT"
 
       # Master refreshes the caches that pull requests restore without saving.
+      # The store cache stays a hand-rolled actions/cache step rather than
+      # setup-node's `cache: pnpm`: the enterprise pull-request jobs above
+      # restore exactly this key and path, and setup-node's built-in cache
+      # uses its own key format — converting this producer would silently
+      # starve their documented restore-only optimization.
       - uses: actions/cache@v4
         with:
           path: ${{ steps.pnpm-store.outputs.path }}
@@ -498,9 +493,14 @@ jobs:
     steps:
       - uses: actions/checkout@v6
 
+      - uses: pnpm/action-setup@v4
+
+      # The Windows lanes deliberately skip the store cache like the required
+      # windows job; an empty cache input disables setup-node's caching.
       - uses: actions/setup-node@v6
         with:
           node-version: ${{ env.PRIMARY_NODE_VERSION }}
+          cache: ${{ matrix.platform == 'linux' && 'pnpm' || '' }}
 
       - name: Report runner capacity
         run: >-
@@ -508,22 +508,6 @@ jobs:
           console.log(JSON.stringify({ arch: process.arch, cpus: os.cpus().length,
           memoryGiB: Math.round(os.totalmem() / 2 ** 30) }))"
 
-      - name: Enable corepack (pnpm)
-        run: corepack enable
-
-      - name: Resolve pnpm store path
-        if: matrix.platform == 'linux'
-        id: pnpm-store
-        run: echo "path=$(pnpm store path --silent)" >> "$GITHUB_OUTPUT"
-
-      - uses: actions/cache@v4
-        if: matrix.platform == 'linux'
-        with:
-          path: ${{ steps.pnpm-store.outputs.path }}
-          key: ${{ runner.os }}-node-${{ env.PRIMARY_NODE_VERSION }}-pnpm-${{ hashFiles('pnpm-lock.yaml') }}
-          restore-keys: |
-            ${{ runner.os }}-node-${{ env.PRIMARY_NODE_VERSION }}-pnpm-
-
       - name: Install (immutable)
         run: pnpm install --frozen-lockfile
 
@@ -598,9 +582,14 @@ jobs:
     steps:
       - uses: actions/checkout@v6
 
+      - uses: pnpm/action-setup@v4
+
+      # Unlike the larger-runner suite, both platforms cache the store here:
+      # the consolidated topology measures cache mechanics as workload.
       - uses: actions/setup-node@v6
         with:
           node-version: ${{ env.PRIMARY_NODE_VERSION }}
+          cache: pnpm
 
       - name: Report runner capacity
         run: >-
@@ -608,27 +597,6 @@ jobs:
           console.log(JSON.stringify({ arch: process.arch, cpus: os.cpus().length,
           memoryGiB: Math.round(os.totalmem() / 2 ** 30) }))"
 
-      - name: Enable corepack (pnpm)
-        run: corepack enable
-
-      - name: Resolve pnpm store path (Linux)
-        if: matrix.platform == 'linux'
-        id: pnpm-store-linux
-        run: echo "path=$(pnpm store path --silent)" >> "$GITHUB_OUTPUT"
-
-      - name: Resolve pnpm store path (Windows)
-        if: matrix.platform == 'windows'
-        id: pnpm-store-windows
-        shell: pwsh
-        run: '"path=$(pnpm store path --silent)" >> $env:GITHUB_OUTPUT'
-
-      - uses: actions/cache@v4
-        with:
-          path: ${{ steps.pnpm-store-linux.outputs.path || steps.pnpm-store-windows.outputs.path }}
-          key: ${{ runner.os }}-node-${{ env.PRIMARY_NODE_VERSION }}-pnpm-${{ hashFiles('pnpm-lock.yaml') }}
-          restore-keys: |
-            ${{ runner.os }}-node-${{ env.PRIMARY_NODE_VERSION }}-pnpm-
-
       - uses: actions/cache@v4
         if: matrix.platform == 'linux'
         with:

.github/workflows/docs-pages.yml

@@ -33,23 +33,12 @@ jobs:
     steps:
       - uses: actions/checkout@v6
 
+      - uses: pnpm/action-setup@v4
+
       - uses: actions/setup-node@v6
         with:
           node-version: ${{ env.PRIMARY_NODE_VERSION }}
-
-      - name: Enable corepack (pnpm)
-        run: corepack enable
-
-      - name: Resolve pnpm store path
-        id: pnpm-store
-        run: echo "path=$(pnpm store path --silent)" >> "$GITHUB_OUTPUT"
-
-      - uses: actions/cache@v4
-        with:
-          path: ${{ steps.pnpm-store.outputs.path }}
-          key: ${{ runner.os }}-node-${{ env.PRIMARY_NODE_VERSION }}-pnpm-${{ hashFiles('pnpm-lock.yaml') }}
-          restore-keys: |
-            ${{ runner.os }}-node-${{ env.PRIMARY_NODE_VERSION }}-pnpm-
+          cache: pnpm
 
       - name: Install (immutable)
         run: pnpm install --frozen-lockfile

.github/workflows/e2e.yml

@@ -61,23 +61,12 @@ jobs:
     steps:
       - uses: actions/checkout@v6
 
+      - uses: pnpm/action-setup@v4
+
       - uses: actions/setup-node@v6
         with:
           node-version: 24
-
-      - name: Enable corepack (pnpm)
-        run: corepack enable
-
-      - name: Resolve pnpm store path
-        id: pnpm-store
-        run: echo "path=$(pnpm store path --silent)" >> "$GITHUB_OUTPUT"
-
-      - uses: actions/cache@v4
-        with:
-          path: ${{ steps.pnpm-store.outputs.path }}
-          key: ${{ runner.os }}-node-24-pnpm-${{ hashFiles('pnpm-lock.yaml') }}
-          restore-keys: |
-            ${{ runner.os }}-node-24-pnpm-
+          cache: pnpm
 
       - name: Install (immutable)
         run: pnpm install --frozen-lockfile

.github/workflows/pi-ai-provider-e2e.yml

@@ -27,23 +27,12 @@ jobs:
     steps:
       - uses: actions/checkout@v6
 
+      - uses: pnpm/action-setup@v4
+
       - uses: actions/setup-node@v6
         with:
           node-version: 24
-
-      - name: Enable corepack (pnpm)
-        run: corepack enable
-
-      - name: Resolve pnpm store path
-        id: pnpm-store
-        run: echo "path=$(pnpm store path --silent)" >> "$GITHUB_OUTPUT"
-
-      - uses: actions/cache@v4
-        with:
-          path: ${{ steps.pnpm-store.outputs.path }}
-          key: ${{ runner.os }}-node-24-pnpm-${{ hashFiles('pnpm-lock.yaml') }}
-          restore-keys: |
-            ${{ runner.os }}-node-24-pnpm-
+          cache: pnpm
 
       - name: Install (immutable)
         run: pnpm install --frozen-lockfile