Move the action from Deno to Node.js and Vite+

AGENTS.md

@@ -10,6 +10,21 @@ comment `@bot` to request an AI-bot review. Wait for green CI and the bot's
 approval on the current head before merging. Never merge without the user's
 explicit permission.
 
-Repository TypeScript and checks use Deno. The composite action uses npm only to
-install the externally distributed Claude Code and Codex command-line tools; do
-not treat those vendor executables as repository TypeScript dependencies.
+# Runtime and checks
+
+The action's TypeScript runs directly on the job image's Node.js (24.2 or
+newer), which strips the types itself: there is no build step and no runtime
+dependency. Keep the sources to erasable syntax and `.ts` imports, which
+`tsconfig.json` enforces. Checks use Vite+: `vp check` formats, lints, and
+type-checks, and `vp test` runs Vitest. Unit tests sit next to the code as
+`src/*.test.ts`; repository-level tests live in `tests/`.
+
+The only config files are `package.json`, `tsconfig.json`, and
+`vite.config.ts`, plus `package-lock.json`. Repo-local lint rules and the rule
+list live in `scripts/project-lint.ts`. Lint disable comments are not allowed;
+fix the source instead.
+
+The composite action uses npm only to install the externally distributed
+Claude Code, Codex, and OpenCode command-line tools, plus Deno for agents that
+check Deno-based repositories; do not treat those vendor executables as
+repository TypeScript dependencies.