Merge remote-tracking branch 'origin/master' into worktree/provider-routed-llm-adapters

# Conflicts:
#	docs/cordis-catalog/events.md
#	docs/cordis-catalog/services.md
#	docs/event-producer-consumer.md
#	docs/module-graph.md
#	packages/context/time-context/tests/time-context.spec.ts
#	packages/cordis/tool-cordis/src/api-catalog.ts
#	packages/core/session/README.md
#	packages/core/session/src/types.ts
#	packages/core/session/tests/surface.spec.ts
#	packages/examples/acp-demo/tests/acp-agent.spec.ts
#	packages/examples/stdio-demo/tests/stdio-agent.spec.ts
#	packages/hooks/hooks-claude/tests/coverage.spec.ts
#	packages/hooks/hooks-codex/tests/coverage.spec.ts
#	packages/session-query/session-query/tests/session-query.spec.ts
#	packages/support/invariants/tests/invariants.spec.ts
#	packages/ui/acp/tests/harness.ts

docs/core-data-structures/session.md

@@ -4,6 +4,14 @@ The in-memory, event-sourced model of [dsh-session](../../packages/core/session)
 
 Source: [`packages/core/session/src/types.ts`](../../packages/core/session/src/types.ts)
 
+## Context framing
+
+`ContextEnvelope` selects the standard tagged projection or preserves a producer-owned complete frame. The latter changes framing only; the event remains a user-role `context/message` in chronological history.
+
+```ts type-equiv
+type ContextEnvelope = 'context' | 'raw'
+```
+
 ## `SessionEventMap` — the event vocabulary
 
 The append-only event types. Merge-extensible: a plugin declares extra event types via declaration merging — e.g. the [compaction seam](compaction.md) adds `compact/start` / `compact/summary` / `compact/end`, and `@deepseek-ai/dsh-hook-protocol` adds log-only `hook/invoked` / `hook/result` provenance for a hook bridge. Like `compact/*`, these are NOT `SurfaceEventType`s (no `surfaceOp`). The generated [persistence log event catalog](../persistence-catalog.md) enumerates every member — core and merged — with its payload, surface badge, and declaration site.
@@ -30,9 +38,16 @@ interface SessionEventMap {
   /**
    * In-session context injection (file-change notices, subdir AGENTS.md,
    * skill content, cron notifications, …). Rendered into the derived history
-   * as tagged synthetic context — NOT a user prompt.
+   * as synthetic context — NOT a user prompt. `envelope: 'raw'` lets a caller
+   * supply its own complete framing; `meta` is persisted JSON hidden from the
+   * model.
    */
-  'context/message': { content: ContentBlock[]; source: MessageSource }
+  'context/message': {
+    content: ContentBlock[]
+    source: MessageSource
+    envelope?: ContextEnvelope
+    meta?: JsonValue
+  }
   /** Raw stream chunk — token-level replay fidelity. */
   'assistant/chunk': { turn: number; step: number; chunk: StreamChunk }
   /**
@@ -223,7 +238,8 @@ export interface SurfaceFoldResult {
 - `user/message` → a user message.
 - `assistant/message` → an assistant message with the event's provider/model provenance and optional adapter-private replay state. Raw `assistant/chunk` events are replay/UI data and are **skipped** in derivation (the assembled message is authoritative). An **empty-content** `assistant/message` is also skipped — a max-tokens step cut off with no content still records an `assistant/message` to host its usage/provenance, but a content-less assistant turn must not enter the provider transcript.
 - `tool/result` → a user message carrying a `tool-result` block.
-- `context/message`, `steering/message` → user-role messages wrapped in a tagged envelope (`<context source="…">…</context>`) at their chronological position — the "system-reminder" pattern; the model distinguishes them from real prompts by the envelope.
+- `context/message` → a user-role message at its chronological position. The default `envelope` is `context`, which wraps content as `<context source="…">…</context>`; `envelope: 'raw'` uses caller-owned framing verbatim. Optional JSON `meta` remains in the event log and is never rendered.
+- `steering/message` → a user-role message wrapped in `<steering source="…">…</steering>` at its chronological position.
 
 Everything else (`turn/*`, `step/*`) is structural and does not project into a message. Token usage is observed on `assistant/message.usage` (the step that produced it); an operational error's step number is on `turn/end.reason` for `kind: 'error'`. Because this unreleased format intentionally has no compatibility promise, seed/load validation rejects request headers without provider+model and assistant messages without provider/model provenance instead of guessing a route for historical data.