docs: rebuild the documentation skill and standards (#2983)

docs/testing.md

@@ -7,13 +7,13 @@ How this repo tests, tier by tier, and the rules that keep a green suite meaning
 ## Tiers
 
 - **Unit** (`pnpm run test`): vitest over package and example specs under their `tests/**` directories plus repository script specs under `scripts/**/*.spec.ts`; tests stay with the code area they exercise. Every registry gets an HMR-safety test (dispose the contributing fiber, assert cleanup). Prefer edge cases, error paths, event ordering, concurrency races, and permanent tests for contract regressions (see `packages/core/agent-loop/tests/contract-regressions.spec.ts`).
-- **Coverage gate** (`pnpm run test:coverage`): the gating run, per-file 100% on `packages/*/*/src`. An uncovered line is often dead code the gate is correctly flagging for deletion, not a missing test to bolt on. Line coverage is necessary, never sufficient — it proves lines ran, not that the feature works as shipped. Per-file 100% on `packages/shell/pwsh-local/src` needs a real `pwsh`: without one its executor suites self-skip and `vitest.config.ts` exempts the file so pwsh-less hosts stay green, while CI runners ship pwsh and enforce the full bar.
+- **Coverage gate** (`pnpm run test:coverage`): the gating run, per-file 100% on `packages/*/*/src`. An uncovered line is often dead code the gate flags for deletion, not a missing test to bolt on. Line coverage is necessary, never sufficient — it proves lines ran, not that the feature works as shipped. Per-file 100% on `packages/shell/pwsh-local/src` needs a real `pwsh`: without one its executor suites self-skip and `vitest.config.ts` exempts the file so pwsh-less hosts stay green, while CI runners ship pwsh and enforce the full bar.
 - **Real-API e2e** (`pnpm run test:e2e`): with-key tests against live provider APIs — the DeepSeek model plus provider-specific smokes that gate on their own keys (`EXA_API_KEY`, `PERPLEXITY_API_KEY`, …); each suite self-skips without its key so keyless CI stays green ([real-API e2e Agent Note](../.agents/notes/implemented/testing/2026-06-19-real-api-e2e-ci.md)).
 - **Owner-local expected output** (`pnpm run test:expected`): keyless assembled CLI/process expectations without a recorded-session round trip. Drivers use `*.expected.e2e.ts` beside `tests/expected/`; CI runs built exports. Package/script expectations use `test`, while browser expectations use `test:web`.
 - **Snapshot** (`pnpm run test:snapshot`): a top-level scenario's recorded `session.jsonl` supplies user input and model replay, then serves as the expected persisted result. Process scenarios start through `dsh`: headless owns one-shot behavior, the SDK owns persistent control, ACP owns automation-protocol behavior, and Web retains browser/ARIA evidence beside the same session. `snapshot.yml` declares the profile, composition/header class, recording policy, exceptional replay or input metadata, and workspace facts. Typed tokens preserve parent/child identity relationships; only header pins own prompt/schema sidecars. A mutating scenario independently compares the complete `workspace.expected/` tree, which record and refresh never rewrite. Use `test:snapshot:record` when a model transcript changes and `test:snapshot:refresh` when replay input remains valid; review every resulting diff.
 - **Web browser snapshot** (`pnpm run test:web`; required Linux PR gate): Chromium compares session-driven output under `snapshots/web/` and UI-only output under `apps/web/tests/expected/`. CI forces read-only `DSH_SNAPSHOT=replay`, never writing expected outputs; record/refresh stay local and every diff is reviewed ([web e2e lane](../.agents/notes/implemented/testing/2026-07-24-web-gui-browser-e2e-lane.md), [CI gate decision](../.agents/notes/implemented/testing/2026-07-30-web-browser-snapshot-ci-gate.md)). `test:web` [builds first](../.agents/notes/implemented/bug-fix/2026-07-28-themed-scrollbars-and-reserved-gutter.md) for plugin CSS.
 
-Session fixtures keep headers and payloads but omit body sequence/time envelopes. Replay synthesizes them; runtime persistence is unchanged. Fixtures use canonical packed rows; [the migrator](../scripts/migrate-packed-session-fixtures.ts) rewrites old layouts.
+Session fixtures keep headers and payloads but omit body sequence/time envelopes. Replay synthesizes them. Fixtures use canonical packed rows; [the migrator](../scripts/migrate-packed-session-fixtures.ts) rewrites old layouts.
 
 ## The with-key policy: inference is cheap here
 
@@ -21,18 +21,18 @@ We are DeepSeek — do not ration real-API tests. A no-key test proves plumbing;
 
 ## Prefer the real implementation over a mock
 
-Mock only the expensive or non-deterministic boundary (LLM adapter, network, clock); keep everything downstream real. A hand-rolled stand-in proves the bridge moves bytes, not that the shipping tool behaves as asserted. Bridge tool-call tests use the scripted mock model with the real tool and executor: `makeBridgeHarness({ withBash: true })` plugs in `dsh-bash-local` and `dsh-tool-bash`, then runs `echo`.
+Mock only the expensive or non-deterministic boundary (LLM adapter, network, clock); keep everything downstream real. A hand-rolled stand-in proves the bridge moves bytes, not that the shipping tool behaves as asserted. Bridge tool-call tests keep the real tool registry and pipeline behind the scripted mock model: `makeBridgeHarness()` mounts the loop, session store, tool registry, and JSONL persistence with a `MockAdapter` as the only mock (packages/acp/acp/tests/harness.ts).
 
 Recovery tests separate pre/post-chunk failures by step and prove failed chunks derive no message or tool side effect. Cover exhaustion, cancellation, policy composition, persistence, status, wire counts, transport-closing idle timeouts, and shipping Loader composition.
 
 ## Verify the world, not the self-report
 
-An e2e assertion re-runs the command or re-reads the file externally; a keyword probe on the agent's own output lets a cheating agent pass. Assert untouched files are byte-identical. e2e tests own their resources: create the harness in the test, dispose in `afterEach` (even on failure/retry/timeout); shared fixtures live in a plain `tests/harness.ts`, never another `*.e2e.ts` (importing a spec re-registers its `describe` and duplicates real API calls).
+An e2e assertion re-runs the command or re-reads the file externally; a keyword probe on the agent's own output lets a cheating agent pass. Assert untouched files are byte-identical. e2e tests own their resources: create it in the test, dispose in `afterEach` (even on failure/retry/timeout); shared fixtures live in a plain `tests/harness.ts`, never another `*.e2e.ts` (importing a spec re-registers its `describe` and duplicates real API calls).
 
 ## Test the real entry path
 
 - Product-visible plugins require a non-unit REAL-composition test. Hand-built `ctx.plugin(...)` suites are insufficient: boot test-only `cordis.yml` through Loader and app/process, mock only external services or nondeterministic inputs, and assert model-visible request/log, durable state, or user-visible output. Keep opt-ins out of shipped defaults.
-- A guard only guards if the regression actually fails it. For a plugin without `inject` (bundle/composition plugins), a Loader smoke stays green when a default export replaces the required named exports — add an explicit `expect('default' in mod).toBe(false)` plus an `unwrapExports` round-trip assertion, and prove it: introduce the regression, watch red, revert.
+- A guard only guards if the regression fails it. For a plugin without `inject` (bundle/composition plugins), a Loader smoke stays green when a default export replaces the required named exports — add an explicit `expect('default' in mod).toBe(false)` plus an `unwrapExports` round-trip assertion, and prove it: introduce the regression, watch red, revert.
 - "Real entry path" means the published artifact: a package `bin` runs built `lib/bin.js` under plain `node`, exposing failures tsx masks (settle races, module resolution, swallowed load failures). The same applies to non-index runtime entries (the worker-thread sibling `lib/worker.cjs`) and singleton modules shared across bundles (`packages/sdk/server/tests/built-scope-carrier.e2e.ts`). Keep the built-artifact smokes green (`packages/examples/*/tests/built-bin.e2e.ts`, `packages/code-runtime/code-runtime-worker-thread/tests/built-lib.e2e.ts`), and assert a genuinely-missing config exits non-zero.
 
 ## Test resolution: source plane only