Add port 8122 for reverse proxy, fix buildx cache, update docs

- Map host 8122 to api container for reverse proxy at momswap.produktor.duckdns.org
- Remove buildx cache_from/cache_to to allow docker build on default driver
- Document reverse proxy setup in frontend integration guide
- Update README with port mapping notes
- bun.lock: add deps from bun install for geo-api-client

Made-with: Cursor

README.md

@@ -56,9 +56,9 @@ COMPOSE_BAKE=true docker compose --profile dev up --watch
 
 Notes:
 
+- `api` service listens on `8122` inside the container, mapped to host `8122` (reverse proxy at `https://momswap.produktor.duckdns.org`).
 - `api` service uses the production `runtime` image target.
 - `api-dev` profile uses the `dev` image target and Docker Compose watch.
-- Build cache is persisted at `.docker/buildx-cache` via `cache_from`/`cache_to`.
 - DB defaults can be overridden via `POSTGRES_DB`, `POSTGRES_USER`, `POSTGRES_PASSWORD`.
 
 ## Frontend