move models.dev drift tests to main-only; add per-alias live smoke matrix

PR CI kept breaking on upstream catalog drift (new model ships on models.dev,
OpenRouter renames an id, etc.) — failures unrelated to the PR's contents.
split the model-alias test suite so PRs only see pure-logic checks, and push
the external-state drift + end-to-end coverage to main.

test organization:
- action/test/models.test.ts keeps pure invariants: openRouterResolve
  completeness and fallback-chain resolution. runs on every PR.
- action/test/models-catalog.main.test.ts gets the 4 network-dependent
  describes (models.dev validity x2, OpenRouter API validity, latest-model
  snapshot). runs only on main push via a dedicated vitest config
  (vitest.main.config.ts + `pnpm test:catalog`).

new CI jobs in .github/workflows/test.yml:
- models-catalog: `pnpm test:catalog` on every main push. detects upstream
  catalog drift so we can react at the next convenient window.
- models-live: 38-entry matrix that invokes the agent harness end-to-end
  against the real provider for each alias in models.ts. generated from
  action/test/list-aliases.ts. runs only on main push AND only when
  resolution-affecting files changed (action/models.ts, action/package.json,
  action/agents/**) — the exact shape of the opus 4.7 incident.

test/run.ts: PULLFROG_MODEL now flows through from process.env so the live
matrix can pin an alias per job without the per-agent default clobbering it.

Made-with: Cursor

vitest.main.config.ts

@@ -0,0 +1,15 @@
+import { defineConfig } from "vitest/config";
+
+// config for main-only tests (see *.main.test.ts). runs the catalog drift
+// suite explicitly; the default vitest.config.ts excludes these files so PR
+// CI stays unaffected by upstream catalog changes.
+export default defineConfig({
+  test: {
+    globals: true,
+    environment: "node",
+    include: ["**/*.main.test.ts"],
+    exclude: ["**/node_modules/**", "**/.temp/**", "**/.pnpm-store/**"],
+    globalSetup: ["./vitest.global-setup.ts"],
+    setupFiles: ["./vitest.setup.ts"],
+  },
+});