Switch local API port to 8122 and keep DB internal.

Update runtime defaults, compose mappings, frontend defaults, and developer docs to use port 8122 while keeping PostGIS reachable only via the internal compose network.

Made-with: Cursor

README.md

@@ -22,11 +22,11 @@ go run ./cmd/api
 
 Primary deployed base URL: `https://momswap.produktor.duckdns.org/`.
 
-Local default (for development): `http://localhost:8080`.
+Local default (for development): `http://localhost:8122`.
 
 Optional environment variables:
 
-- `ADDR` (default `:8080`)
+- `ADDR` (default `:8122`)
 - `ADMIN_PUBLIC_KEY` (bootstrap initial inviter/admin user)
 
 ## Docker Compose
@@ -40,7 +40,7 @@ COMPOSE_BAKE=true docker compose up --build -d
 This starts:
 
 - `db` (`postgis/postgis`) on `5432`
-- `api` on `8080`, wired with `DATABASE_URL` to the `db` service
+- `api` on `8122`, wired with `DATABASE_URL` to the `db` service
 
 Stop the service:
 
@@ -74,7 +74,7 @@ go run ./cmd/api
 Then visit:
 
 - Production: `https://momswap.produktor.duckdns.org/web/`
-- Local: `http://localhost:8080/web/`
+- Local: `http://localhost:8122/web/`
 
 ## API client library