Make the vision judge discover cost-effective OpenRouter models

Add openrouter_judge.py to rank live image+JSON models by advertised price,
with ordered fallbacks, auth-error handling and auto selection. Wire both judges
to --model auto, record the model used, and add fake-catalogue/mocked-call
tests. Re-run the judges with the valid key: 13/13 screen designs match, 0 diff;
the Forward+ A/B report records the selected model and ~$0.006 spend. Headless
231/231, Python 94/94.

DONE.md

@@ -1311,3 +1311,28 @@ path.
       to Compatibility instead of failing to start). Verified with the preset in the project
       root: `godot --headless --path . --quit-after 5` exits 0 and starts the game; an exported
       HQ binary also boots with Vulkan Forward+ under Xvfb.
+
+## Vision judge reliability (v0.7.2)
+
+Completed 2026-11-01. The judge now discovers the cheapest current OpenRouter image+JSON model (falling back through known candidates), reports the model used, and uses the valid key. Full screen-design judge: 13/13 match, 0 diff.
+
+The judge failed with an invalid-key HTTP 400 even though the `.env` key was later
+valid, and a hard-coded model can disappear or be unavailable. Make the judge discover
+current OpenRouter vision models, prefer cheap/structured-output-capable ones, and fall
+back when a provider rejects a request.
+
+- [x] Add `tools/openrouter_judge.py`: query `/api/v1/models`, filter image-input models
+      with `response_format` support, rank by estimated token/image cost, and keep a
+      small known-good fallback list.
+- [x] Let both `screen_designs.py judge` and `scene_concepts.py realism --judge` use
+      `--model auto` (the new default), retry a transient provider error once, and move
+      to the next model on model/provider failures. An invalid key fails with exit 2.
+- [x] Print/report the selected model(s) and fallback order; the judge JSON records the
+      selected model and the selected-parameter cost is inferred from the public catalogue.
+- [x] Add `tools/test_openrouter_judge.py` with a fake catalogue and mocked calls for ranking,
+      explicit/env override, invalid-key stop, transient retry and provider fallback.
+- [x] Re-run the full screen-design judge and the Forward+ A/B judge with the valid
+      `OPENROUTER_API_KEY`: screen designs are **13/13 match, 0 diff**; the Forward+ report
+      records the selected model and ~$0.006 spend.
+- [x] Update `docs/asset-tooling.md`, `MEMORY.md`, `README.md` and `CHANGELOG.md`; the
+      public catalogue picks the cheapest image+JSON model (`z-ai/glm-5.3-flash` at run time).