ci: use process-safe coverage pools

.github/workflows/ci.yml

@@ -50,13 +50,17 @@ jobs:
         with:
           node-version: ${{ env.PRIMARY_NODE_VERSION }}
 
+      - name: Enable corepack and resolve pnpm store path
+        id: pnpm-store
+        run: |
+          corepack enable
+          echo "path=$(pnpm store path --silent)" >> "$GITHUB_OUTPUT"
+
       # Pull requests consume the default-branch cache but do not put cache
       # compression and upload on the paid latency-critical path.
       - uses: actions/cache/restore@v4
         with:
-          # Cache the versioned store through its stable parent so selecting
-          # the current pnpm store does not require a separate runner step.
-          path: ~/.local/share/pnpm/store
+          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-
@@ -70,7 +74,6 @@ jobs:
 
       - name: Install dependencies and prepare bubblewrap
         run: |
-          corepack enable
           pnpm install --frozen-lockfile &
           install_pid=$!
           bash scripts/prepare-ci-bubblewrap.sh &