feat(backend): scaffold PodMan agent pipeline + token server

Express server with /health and a LiveKit token endpoint. Module skeletons
for the full loop: vision (Gemini), GitHub fusion, collision detector (pure,
testable), intervention engine, and continual-learning memory store. Approve
native build scripts (esbuild/genai/protobufjs) at the workspace root.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

shared/src/index.ts

@@ -1,10 +1,6 @@
 export type { Pod, Engineer } from './pod.js';
 export type { EngineerContext } from './engineer.js';
-export type {
-  Collision,
-  CollisionSeverity,
-  GithubStateSnapshot,
-} from './collision.js';
+export type { Collision, CollisionSeverity, GithubStateSnapshot } from './collision.js';
 export type {
   Intervention,
   InterventionKind,