Mitigate CI cache timeouts and wire venue door-staff dialogue

- Drop actions/cache@v4 from the checks job: the Gitea runner cannot reach
  GitHub's cache service (/twirp/...CacheService timeouts, ~2min retries);
  Godot import is fast enough without it. Add GODOT_SILENCE_ROOT_WARNING=1.
- Document the cache situation and re-enable path in docs/RELEASING.md
- VenueScenario.door_staff_line(context, rng): seeded-random venue lines
- GameManager logs id/ticket/wand-check, refusal, and prohibited-item lines
  from the venue scenario (Joke Shop flavor) during inspection/screening
- Test coverage: all Joke Shop contexts, unknown contexts, empty venues,
  deterministic seeded picks (54 tests pass)

docs/RELEASING.md

@@ -40,6 +40,11 @@ The repository ships a Gitea Actions workflow (`.gitea/workflows/build.yml`):
 For tag builds, set a repo secret named **`GITEA_TOKEN`** (write:repository scope).
 Without it the workflow still builds and tests, but the release publish step fails.
 
+> **No `actions/cache` for now:** the runner has no local actions-cache service, so
+> `actions/cache` times out against GitHub's cache API. We dropped it (Godot import
+> is only ~4s). If a host admin later enables Gitea `[cache.actions]` with a cache
+> server, the step can be reintroduced.
+
 > The workflow lives in `.gitea/workflows/` (Gitea's canonical path). The old
 > `.github/workflows/ci.yml` was removed to avoid double runs on hosts that scan
 > both directories.