Merge remote-tracking branch 'origin/rfc/pty' into worktree/pr467-retarget-latest-master

.agents/notes/implemented/testing/2026-06-19-acp-snapshot-tests.md

@@ -18,6 +18,8 @@ A snapshot test boots the real ACP example, drives its stdio protocol from a det
 
 Each scenario's `session.jsonl` is harvested from a real run. `assistant/chunk` events reproduce the model streams; tool, message, and boundary events capture the harness behavior. One ordinary session artifact therefore serves as both replay source and behavioral expected output.
 
+When a scenario pins an alternative physical storage layout, its fixture is mechanically derived from a real unpacked counterpart. The scenario test requires every intended storage-row kind and exact event-for-event equality after decoding before the ordinary replay and log comparison proves that the assembled process consumes and reproduces that layout.
+
 ### Replay derives the model script from the log
 
 `llm-replay` short-circuits the provider-agnostic `llm/stream` waterfall. `deriveReplayScript()` groups recorded chunks by `(turn, step)` and serves one group per model call. The loop makes one stream call per step, so the grouping is exact and includes error finish chunks without special handling.

.agents/notes/implemented/testing/2026-07-08-shared-acp-snapshot-package.md

@@ -18,7 +18,7 @@ The machinery lives in [`packages/support/acp-snapshot`](../../../../packages/su
 
 **`src/normalize.ts`** — the pure normalizers, hook-free by policy: when a future event carries a new volatile field (an approval duration, say), the shared normalizer learns it in the same change, keeping one home for what "normalized" means rather than per-suite scrub extensions.
 
-**`src/suite.ts`** — the `Scenario` type and `defineAcpSnapshotSuite(options)`, registering the per-scenario compares, record/refresh fixture write-back, the header pin with its live uniformity guard, and the fixture guard block (no orphan scenario dirs, required files present, exactly one pin per class, every JSONL a `scrubSystemPrompts` fixed point, non-pinning fixtures also `scrubRequestHeaders` fixed points). A scenario directory's `session.jsonl` plus contiguous `session.<n>.jsonl` siblings are its ordered primary/child inventory, so the scenario table declares policy without duplicating a child count. The pinned-header contract ([pinned-header Agent Note](2026-07-06-pin-request-header-content-in-one-scenario.md)) is per-suite: each header class flags exactly one `pinsHeader` scenario, whose `system-prompt.expected.md` and JSONL tool list split the composed header into reviewable artifacts; the uniformity guard compares both against every live header in that class. A pinning scenario declares any legitimate changed-header count, and its Markdown artifact records every full changed prompt. The pure helpers (`sessionFixtureNames`, `fixtureContext`, `normalizedHeaders`, `normalizedSystemPrompts`, `formatSystemPromptSnapshot`, `headerChangeCount`) are exported from the module for direct unit coverage.
+**`src/suite.ts`** — the `Scenario` type and `defineAcpSnapshotSuite(options)`, registering the per-scenario compares, record/refresh fixture write-back, the header pin with its live uniformity guard, and the fixture guard block (no orphan scenario dirs, required files present, exactly one pin per class, every JSONL a `scrubSystemPrompts` fixed point, non-pinning fixtures also `scrubRequestHeaders` fixed points). Refresh expands packed timing envelopes before aligning existing volatile event times, so switching between packed and unpacked layouts cannot shift later records; fresh chunk-fragment arrays remain authoritative because their boundaries are replay behavior. A scenario directory's `session.jsonl` plus contiguous `session.<n>.jsonl` siblings are its ordered primary/child inventory, so the scenario table declares policy without duplicating a child count. The pinned-header contract ([pinned-header Agent Note](2026-07-06-pin-request-header-content-in-one-scenario.md)) is per-suite: each header class flags exactly one `pinsHeader` scenario, whose `system-prompt.expected.md` and JSONL tool list split the composed header into reviewable artifacts; the uniformity guard compares both against every live header in that class. A pinning scenario declares any legitimate changed-header count, and its Markdown artifact records every full changed prompt. The pure helpers (`sessionFixtureNames`, `fixtureContext`, `normalizedHeaders`, `normalizedSystemPrompts`, `formatSystemPromptSnapshot`, `headerChangeCount`) are exported from the module for direct unit coverage.
 
 ## Alternatives considered