docs(363): sweep the scan-flow drift the re-review caught

The fix commit softened the script's scan-409 wording + dropped ?deep=true but
left the docs describing the old behavior. Match them:
- docs/e2e-local.md: POST .../scan (no ?deep; note local scans always ForceScan)
  + "409, deterministic bar a tiny residual TOCTOU gap" (was "guaranteed 409")
- docs/ci-cd.md: same "guaranteed 409" -> "409 (deterministic bar ...)"

Docs-only; harness behavior unchanged (still 38/38 green, deterministic).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

docs/ci-cd.md

@@ -301,8 +301,9 @@ image's ffmpeg, to exercise two `IEntityLocker` contracts **deterministically**
 racing request once the lock is *provably* held, never a sleep-and-hope): (a) the **library-scan
 "already scanning" 409** — seed ~60 tiny clips into the built-in Shows library so the scanner
 subprocess runs a few seconds, poll `GET /libraries/scan-status` until the library shows active (that
-window is a strict subset of the scan lock's held window), then a second `POST .../scan` is a
-guaranteed 409; (b) the **external-collections "already scanning" 409** — the per-family lock is taken
+window is a strict subset of the scan lock's held window), then a second `POST .../scan` is a 409
+(deterministic bar a tiny residual TOCTOU gap the multi-second scan covers); (b) the
+**external-collections "already scanning" 409** — the per-family lock is taken
 synchronously *before* the 202, so the 202 proves it held, and pointing the seeded source at a
 non-routable address keeps the background sync hung so the window stays open. No new CI step or
 dependency: ffmpeg ships in the toolchain image, and python3 was already a harness dependency

docs/e2e-local.md

@@ -161,11 +161,12 @@ What it covers. Most assertions are curl-only (no seeded media / ffmpeg / browse
   API can't create straight into the running instance's DB via python3's stdlib `sqlite3` (whose
   busy-timeout retry serializes behind the app's writer):
   - **library-scan "already scanning"**: seed ~60 tiny ffmpeg clips into the built-in Shows library
-    (Id=2) so the scanner subprocess runs a few seconds → `POST .../scan?deep=true` `202` → poll
-    `GET /libraries/scan-status` until library 2 shows active (that window is a strict subset of the
-    scan lock's held window — `ScannerProxyService.StartScan` fires *after* `LockLibrary`, `EndScan`
-    *before* `UnlockLibrary`) → a second `POST .../scan` is a guaranteed `409`. Self-skips (advisory)
-    if ffmpeg is absent.
+    (Id=2) so the scanner subprocess runs a few seconds → `POST .../scan` `202` (local scans always
+    ForceScan, so no `deep` needed) → poll `GET /libraries/scan-status` until library 2 shows active
+    (that window is a strict subset of the scan lock's held window — `ScannerProxyService.StartScan`
+    fires *after* `LockLibrary`, `EndScan` *before* `UnlockLibrary`) → a second `POST .../scan` is a
+    `409`, deterministic bar a tiny residual TOCTOU gap the multi-second scan covers. Self-skips
+    (advisory) if ffmpeg is absent.
   - **external-collections "already scanning"**: seed a Jellyfin media-source row pointing at a
     non-routable address (so the background sync hangs and the per-family lock stays held). The lock
     is taken synchronously *before* the `202`, so the `202` proves it held → `collections-scan-status`