Integrate canonical architecture: two-process backend + LiveKit agent

Promote all 12 staged canonical files from docs/generated/files/ to their
live paths, creating the full PodMan architecture:

Backend:
- server.ts: HTTP service (token mint, sync-PR, outcome recording, /health, WS relay)
- agent.ts: worker joining LiveKit room, grabbing screenshare frames at ~1fps
- agent/podman.ts: orchestrator loop (vision -> collision detection -> intervention)
- env.ts: flat env var accessors replacing nested stub
- vision/gemini.ts: JPEG -> Gemini vision -> EngineerContext (real implementation)
- collision/detector.ts: fused vision+GitHub collision detection (the moat)
- github/client.ts: Octokit wrapper with caching + sync PR creation
- memory/store.ts: extended with recordObservation/recordCollision/recordIntervention/recordOutcome helpers
- memory/vectors.ts: stub for Voyage+Atlas vector recall (Loop A)
- memory/policy.ts: stub for intervention policy gate (Loop B)
- voice/live.ts: stub for Gemini Live TTS voice output

Shared:
- messages.ts: LiveKit data-channel wire protocol (DataMessage, InterventionOutcome, TeamModel, LocalGitReport)
- index.ts: re-exports messages module

Frontend:
- livekit/useScreenPublish.ts: hook for joining pod and publishing screenshare
- livekit/useInterventions.ts: hook for receiving collision cards and responding
- lib/api.ts: fetchToken + postOutcome HTTP helpers

Database:
- database/init.ts: MongoDB Atlas collections + indexes + vector search index

Infra:
- infra/.do/app.yaml: DO App Platform spec (static_site + service + worker)

Retire stubs superseded by canonical decomposition:
- backend/src/index.ts (replaced by server.ts)
- backend/src/intervention/engine.ts (logic now in agent/podman.ts)
- backend/src/livekit/token.ts (token minting now in server.ts)

Install missing dependencies: @livekit/rtc-node, sharp, mongodb, ws, @types/ws

Type error fixes:
- vision/gemini.ts: use MediaResolution.MEDIA_RESOLUTION_LOW enum value (not string literal)
- agent/podman.ts: wrap SuggestedActionKind into { kind: action } SuggestedAction object

All packages pass pnpm -r typecheck and pnpm -r build.

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

backend/src/agent.ts

@@ -0,0 +1,79 @@
+import {
+  Room,
+  RoomEvent,
+  TrackKind,
+  TrackSource,
+  VideoStream,
+  VideoBufferType,
+  dispose,
+  type RemoteTrack,
+  type RemoteTrackPublication,
+  type RemoteParticipant,
+} from '@livekit/rtc-node';
+import sharp from 'sharp';
+import { AccessToken } from 'livekit-server-sdk';
+import { env } from './env.js';
+import { PodMan } from './agent/podman.js';
+
+const POD_ROOM = process.env.POD_ROOM ?? 'demo-pod';
+const SAMPLE_INTERVAL_MS = 1000; // ~1 fps to the vision model
+
+async function agentToken(room: string): Promise<string> {
+  const at = new AccessToken(env.LIVEKIT_API_KEY, env.LIVEKIT_API_SECRET, {
+    identity: 'podman-agent',
+    name: 'PodMan',
+    ttl: '4h',
+  });
+  at.addGrant({ roomJoin: true, room, canPublish: true, canSubscribe: true, canPublishData: true });
+  return at.toJwt();
+}
+
+async function main() {
+  const room = new Room();
+  const podman = new PodMan(room, POD_ROOM);
+  await room.connect(env.LIVEKIT_URL, await agentToken(POD_ROOM), {
+    autoSubscribe: true,
+    dynacast: true,
+  });
+  await podman.start();
+  console.log(`[agent] PodMan joined room ${POD_ROOM}`);
+
+  const lastSent = new Map<string, number>();
+
+  room.on(
+    RoomEvent.TrackSubscribed,
+    (track: RemoteTrack, pub: RemoteTrackPublication, participant: RemoteParticipant) => {
+      if (track.kind !== TrackKind.KIND_VIDEO || pub.source !== TrackSource.SOURCE_SCREENSHARE) return;
+      const id = participant.identity;
+      const stream = new VideoStream(track);
+      void (async () => {
+        for await (const event of stream) {
+          const now = Date.now();
+          if (now - (lastSent.get(id) ?? 0) < SAMPLE_INTERVAL_MS) continue; // THROTTLE
+          lastSent.set(id, now);
+          const rgba = event.frame.convert(VideoBufferType.RGBA);
+          const jpeg = await sharp(Buffer.from(rgba.data), {
+            raw: { width: rgba.width, height: rgba.height, channels: 4 },
+          })
+            .resize({ width: 1280, withoutEnlargement: true })
+            .jpeg({ quality: 70 })
+            .toBuffer();
+          await podman.onScreenFrame(id, jpeg);
+        }
+      })();
+    },
+  );
+
+  const shutdown = async () => {
+    await room.disconnect();
+    await dispose();
+    process.exit(0);
+  };
+  process.on('SIGINT', shutdown);
+  process.on('SIGTERM', shutdown);
+}
+
+main().catch((e) => {
+  console.error('[agent] fatal', e);
+  process.exit(1);
+});