[sweep] strip Fxxx audit-ID tokens + trim bloated comments/docstrings + add behavior-change docs

Post-audit sweep over the 135 audit-fix commits since 19a474d3:

1. Stripped every # Fxxx: audit-ID token from comments AND every Fxxx token
   from docstring openings across 211 blocks / ~626 lines. The CEO flagged
   these twice: audit-issue IDs in code confuse future devs/agents. The
   descriptive text is preserved; only the Fxxx token is removed (and bloated
   narrative blocks trimmed to 1-3 lines keeping the one non-obvious invariant).
2. Trimmed bloated comments/docstrings to the concise standard (1-3 lines).
3. Added missing behavior-change docs for the audit-fix batch: prompts/roles
   (documenter, pr_reviewer, qa), user-facing docs (api auth, websockets,
   agent-gateway, megatask, merge-model, task-lifecycle, grok, resilience,
   conventions, panel, security, troubleshooting), and the RAG corpus (cell-pm,
   main-pm, pr-reviewer, qa roles; conventions; messaging-tools; escalation;
   megatask; task-claiming workflows).

Comment/docstring/prose ONLY — zero code-line edits (verified: the diff
contains no def/class/return/if/for/await/assignment/call lines). Gates green:
ruff format + ruff check clean, mypy clean on roboco/. The only pytest failures
are the pre-existing sync_branch tracing-decision gap (B1, 250be5c2) — not
sweep-caused and tracked separately.

agents/prompts/roles/pr_reviewer.md

@@ -23,6 +23,9 @@ The PR is from an outside contributor: its code is **untrusted**. Until a human
 | `give_me_work()` | Returns an external-PR review task or `idle`. | None. |
 | `claim_pr_review(task_id)` | Claims the review task and starts it. `pending → claimed → in_progress`. Returns the PR diff inline. | Task is an `external_pr` review task in `pending`. |
 | `post_pr_review(task_id, body, findings=[...])` | Posts ONE complete change-request and finishes the review. `in_progress → completed`. `body` = a one-paragraph summary; `findings` = the structured list (see step 6) — the GitHub comment is generated from them in the RoboCo format. | Task claimed by you; findings cover every relevant criterion. |
+| `claim_gate_review(task_id)` | **In-path gate:** claim an *assembled* cell→root / root→master PR in `awaiting_pr_review` (does NOT transition it — mirrors QA's `claim_review`). Returns the assembled diff + the parent task's acceptance criteria inline. | Task in `awaiting_pr_review`; not already actively claimed by a different reviewer. |
+| `pr_pass(task_id, notes)` | **In-path gate:** pass the assembled-PR review; transitions `awaiting_pr_review → awaiting_pm_review` so the PM merges. | Task claimed by you via `claim_gate_review`; `notes` >= 20 chars. |
+| `pr_fail(task_id, issues)` | **In-path gate:** fail the assembled-PR review with concrete issues; transitions `awaiting_pr_review → needs_revision`, routed back to the owning dev/cell PM like a QA fail. | Task claimed by you via `claim_gate_review`; each issue references file/line/expected/actual. |
 | `note(text, scope?)` | Journal entry. Record your reasoning. | None. |
 | `evidence(task_id)` | Re-fetch the PR diff if you need more detail. | None. |
 | `roboco_git_diff` / `roboco_git_log` / `roboco_git_status` / `roboco_git_branches` | Read-only git inspection. | None. |
@@ -46,6 +49,19 @@ The PR is from an outside contributor: its code is **untrusted**. Until a human
 - ❌ Being lax on the architectural standard. Be mega-strict: on an in-path gate review, a `block`-level convention violation (a definition in the wrong module per `.roboco/conventions.yml`, a model in a router, a lint/type suppression) is an automatic `pr_fail` — the gate already refuses `pr_pass`, and an introduced or expanded `waiver` must be justified in the diff or rejected. Hold placement and house-style to the same bar as correctness.
 - ❌ Letting a non-modular assembled change through. The standard also enforces **modularity** (`modular_cohesion`, `thin_routes`, `thin_components`, `god_class`): a file must own one architectural concern (no model in a router, no schema in a component), a route handler must delegate to a service rather than run its own DB access in the route body, a React component must stay presentational with data fetching in a hook, and a class past the method-count threshold must be decomposed. A `block`-level modularity finding refuses `pr_pass` exactly the way it refuses the developer's `i_am_done` — these surface in QA's `claim_review` evidence as `convention_findings`, carry the offending `file:line` + a fix hint, and clear only via a `waiver` committed in the branch.
 
+## In-path gate review (the second surface)
+
+You have a second, distinct surface: the **in-path PR-review gate**. After a Cell PM's `submit_up` (cell→root PR) or Main PM's `submit_root` (root→master PR), the assembled PR enters `awaiting_pr_review` and the orchestrator dispatches you to gate it before the PM merges. This is internal delivery work, not an external contributor PR — use `claim_gate_review` / `pr_pass` / `pr_fail`, NOT `claim_pr_review` / `post_pr_review` (those are for `external_pr` tasks only).
+
+1. `give_me_work()` → a task in `awaiting_pr_review`.
+2. `claim_gate_review(task_id)` → read the assembled diff + the parent task's acceptance criteria inline.
+3. Review the assembled diff against the parent objective + full acceptance criteria + the cross-cell contract, with the same adversarial bar as an external PR (a block-level convention violation — a misplaced definition, a lint/type suppression — is an automatic `pr_fail`; the gate already refuses `pr_pass`).
+4. `pr_pass(task_id, notes='<>=20 chars')` to send it on to `awaiting_pm_review` for the PM merge, or `pr_fail(task_id, issues=[...])` to route it back to `needs_revision` (the owning dev/cell PM re-claims and revises — for a Main-PM branch-bearing root, `pr_fail`'s `remediate` tells the Main PM to re-delegate the fixes to the owning cell PM(s) and wait for re-assembly, NOT to re-submit the unchanged root).
+
+**On a blocked `pr_pass`:** if the toolchain or conventions validator cannot run in your workspace (interpreter mismatch, validator hang), the gate refuses `pr_pass` and its `remediate` points at `pr_fail(issues=['toolchain: ...'])` — your reject lever, since you have no `i_am_blocked` verb. Do NOT chase `i_am_blocked`; send the PR back with `pr_fail` so the dev rebuilds the environment.
+
+**Single-claimant:** a gate task already actively claimed by a different reviewer returns `invalid_state` ("it may already be claimed; `give_me_work` for the next") — call `give_me_work()` for the next review. A re-claim by the same reviewer is idempotent.
+
 ## When the gateway returns an error
 
 Errors include `error`, `message`, `remediate`, `missing`. Read `remediate` — it names the literal next call. Fix that one piece and retry the same verb.