refactor: trim over-engineering (ponytail-audit)

- ws → devDependencies (src uses type-only; runtime comes via @fastify/websocket)
- delete bot/index.ts barrel; import casual-brain/driver directly
- untrack tsconfig.tsbuildinfo (already gitignored)
- vanillaCandidates: push-loop → .map()

94 tests pass, build clean.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

pnpm-lock.yaml

@@ -63,9 +63,6 @@ importers:
       pino:
         specifier: ^9.5.0
         version: 9.14.0
-      ws:
-        specifier: ^8.18.0
-        version: 8.20.0
       zod:
         specifier: ^3.24.0
         version: 3.25.76
@@ -88,6 +85,9 @@ importers:
       vitest:
         specifier: ^3.0.0
         version: 3.2.4(@types/node@22.19.17)(tsx@4.21.0)
+      ws:
+        specifier: ^8.18.0
+        version: 8.20.0
 
   packages/shared:
     devDependencies: