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)

.gitea/workflows/build.yml

@@ -11,6 +11,9 @@ jobs:
   checks:
     name: Import + headless tests
     runs-on: ubuntu-latest
+    env:
+      # The container runs as root; silence the recurring engine notice.
+      GODOT_SILENCE_ROOT_WARNING: "1"
     steps:
       - uses: actions/checkout@v4
 
@@ -21,12 +24,6 @@ jobs:
           unzip -qo /tmp/godot.zip -d /tmp/godot-bin
           sudo install /tmp/godot-bin/Godot_v4.3-stable_linux.x86_64 /usr/local/bin/godot
 
-      - name: Cache imported assets
-        uses: actions/cache@v4
-        with:
-          path: .godot
-          key: godot-import-${{ hashFiles('project.godot', 'src/**/*.gd', 'content/**/*.json') }}
-
       - name: Import project (build class cache)
         run: godot --headless --import
 
@@ -54,6 +51,8 @@ jobs:
     if: startsWith(github.ref, 'refs/tags/') || github.event_name == 'workflow_dispatch'
     runs-on: ubuntu-latest
     needs: checks
+    env:
+      GODOT_SILENCE_ROOT_WARNING: "1"
     steps:
       - uses: actions/checkout@v4