Export venues as editor-authorable .tres resources

- tools/export_venues.gd (SceneTree script) saves the three factory scenarios to
  content/venues/<id>.tres via ResourceSaver. The factory stays the source of truth;
  the exported files are what an editor workflow would edit and ship.
- New tests load the files back and check that id, name, event pool, profiles,
  policy (ID/wand), equipment, door-staff lines, shift phases, and locations all
  survive. They also fail when the exported files are missing or stale, so the
  export is re-run after content changes.
- GUT is consciously not adopted: the custom headless runner already covers 157
  assertions without an editor plugin and keeps CI dependency-free. Recorded in
  DONE.md.
- TODO: the planned backlog is complete; only optional future ideas remain.
- README/MEMORY updated. Version 0.2.16.

DONE.md

@@ -583,3 +583,15 @@ Completed 2026-10-31 (working tree). 30 Python tooling tests pass; the live judg
       capture + reference design to a vision model, classes verdicts as
       match/review/diff with a confidence threshold, supports `--dry-run`, `--json`,
       `--only`, and `--model`, and reads the repo `.env` for the API key.
+
+## Tooling (when an editor workflow exists)
+
+Completed 2026-10-31 (working tree). Headless **157/157**; the exported `.tres` venues round-trip through the resource loader.
+
+
+- [x] Author venues as `.tres` resources: `tools/export_venues.gd` writes
+      `content/venues/<id>.tres` from the factory, and a test loads them back to check
+      nothing is lost (events, profiles, policy, phases, door lines, locations).
+- [x] GUT decision: **not adopted.** The custom headless runner (`src/test/test_runner.gd`)
+      already covers 157 assertions without an editor plugin, runs in CI, and keeps the
+      project dependency-free; adding GUT would duplicate coverage and require the editor.