ci: fold the four daily patrols into one fleet-patrols.yml workflow

required-set-patrol, platform-checklist-watchdog, release-coverage-patrol
and board-snapshot become four jobs of .github/workflows/fleet-patrols.yml.
Each job keeps the retired file's steps, permissions, concurrency group
and env byte-for-byte; a job-level `if:` gates it to its own cron
(github.event.schedule), workflow_dispatch takes a `patrol` input to fire
one job by hand, and the pull_request trigger is the union of the four
retired filters.

The two gates that read those files by name follow the rename:
check-required-contexts' PATROL_WORKFLOW and the platform-checklist
watchdog pin, whose allowed pull_request path list is now the frozen
union (its self-test drives the widened and the narrowed shapes). The
anchor renderer's published preamble, the archiver's adopt list and the
two platform-checklist docs name the new file.

Claude-Session: https://claude.ai/code/session_01JQwxbW8nFvKeVjgKv8RTwH
Co-authored-by: Claude <noreply@anthropic.com>

Author: claude

.github/workflows/board-snapshot.yml

@@ -211,7 +211,7 @@ Why this shape:
   census and not a verdict). Adding anchors never reds; ⛔ lowering a floor is
   MAINTAINER-ONLY. ⚠️ Note what a red here reaches: `check:platform-checklist` is not
   CI-wired (see "Operating cadence"), so it reaches whoever runs the gate — **not every
-  PR** — plus the daily `platform-checklist-watchdog` workflow, which files or refreshes
+  PR** — plus the daily `platform-checklist-watchdog` job of `fleet-patrols.yml`, which files or refreshes
   one issue when the gate is red.
 - **`why` is the debt marker.** A recipe exists because stock fixtures cannot demonstrate
   something — the same discipline as a coverage waiver. Landing the fixture in the
@@ -433,7 +433,7 @@ checklist drift. It runs on a **manual / periodic cadence** instead. Run
 - **alongside a `checklist-author`** (find gaps) **or `checklist-test`** (execute items).
 
 A red gate does have a reporting channel, and it is not this cadence:
-[`.github/workflows/platform-checklist-watchdog.yml`](../../../.github/workflows/platform-checklist-watchdog.yml)
+the `platform-checklist-watchdog` job of [`.github/workflows/fleet-patrols.yml`](../../../.github/workflows/fleet-patrols.yml)
 runs `pnpm check:platform-checklist` on `main` daily and files or refreshes one issue when
 it is red (⛔ and does nothing when it is green). That closes the visibility half only —
 the cadence above is still how the gate gets run *before* a red can matter.

.github/workflows/fleet-patrols.yml

@@ -14,7 +14,7 @@ contract.
 **Who sees a red gate.** `pnpm check:platform-checklist` is not wired into per-PR CI (a
 standing maintainer decision — see the README's "Operating cadence"), so the channel that
 sees its red is
-[`.github/workflows/platform-checklist-watchdog.yml`](../../../.github/workflows/platform-checklist-watchdog.yml):
+the `platform-checklist-watchdog` job of [`.github/workflows/fleet-patrols.yml`](../../../.github/workflows/fleet-patrols.yml):
 it runs the gate on `main` daily, files or refreshes exactly one issue when the gate is red,
 and does nothing at all when it is green.