docs: finalize PodMan architecture and write full integration specs

Replaces v1 plan with locked architecture:
- Hermes orchestrator: POST /ingest → Gemini Vision → MongoDB → event detection → Gemini Live 2.5 voice via LiveKit Agents
- Four MongoDB collections: engineer_states, ownership_map, events, nudges
- Continual learning via ownership_map persisting across sessions

New files: docs/idea.md, docs/gemini.md, docs/livekit.md, docs/mongodb.md, docs/digitalocean.md, docs/demo-setup.md
Updated: README.md, docs/PLAN.md (12-hour build plan), database/README.md, infra/README.md, .env.example

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01FFbfi4Cmb7BY75Wtne7bZn

infra/README.md

@@ -1,22 +1,34 @@
 # infra
 
-Deploy targets for PodMan (DigitalOcean prize track).
+Deploy targets for PodMan on DigitalOcean.
 
-- `Dockerfile` — builds the backend agent from the monorepo root.
-- `app.yaml` — DigitalOcean App Platform spec (auto-deploy on push to `main`).
+- `Dockerfile` — builds the Hermes backend from the monorepo root
+- `app.yaml` — DigitalOcean App Platform spec (Hermes web service + frontend static site)
+
+Full deploy spec and env var reference in [`docs/digitalocean.md`](../docs/digitalocean.md).
+
+## Local development
+
+```bash
+pnpm --filter backend dev    # Hermes on :8787
+pnpm --filter frontend dev   # PWA on :5173
+```
 
 ## Local container
 
 ```bash
-docker build -f infra/Dockerfile -t podman-backend .
-docker run --env-file .env -p 8787:8787 podman-backend
+docker build -f infra/Dockerfile -t podman-hermes .
+docker run --env-file .env -p 8787:8787 podman-hermes
 ```
 
-## DigitalOcean
+## DigitalOcean deploy
 
 ```bash
 doctl apps create --spec infra/app.yaml
 ```
 
-Set the `SECRET` env vars (LiveKit, Gemini, GitHub, Atlas, Voyage) in the DO
-dashboard or via `doctl` after the app is created.
+Set secret env vars (LiveKit, Gemini, MongoDB) in the DO dashboard after app creation.
+
+## Fallback (demo safety)
+
+If DO deploy is flaky on stage, run Hermes locally. The PWA defaults to `http://localhost:8787` via `VITE_BACKEND_URL` fallback — no code change needed.