Docker-AIO: one image per database

Dockerfile builds warp-aio on SQLite, Dockerfile.PocketBase builds
warp-aio-pocketbase and Dockerfile.PostgreSQL builds warp-aio-postgresql
with PostgreSQL bundled. The database driver and connection string now
come from the image, so the SQLite and PocketBase images no longer carry
PostgreSQL (103 MB instead of 149 MB). The AIO compose files point at
their own Dockerfile and image, and the entrypoint refuses to start an
embedded PostgreSQL in an image that has none.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

Docker-AIO/docker-compose.postgresql.yml

@@ -21,16 +21,12 @@ services:
   warp:
     build:
       context: ..
-      dockerfile: Docker-AIO/Dockerfile
-    image: warp-aio:latest
+      dockerfile: Docker-AIO/Dockerfile.PostgreSQL
+    image: warp-aio-postgresql:latest
     restart: unless-stopped
-    # PostgreSQL's fast shutdown runs after the homeserver's; give both time.
+    # PostgreSQL stops after the homeserver; give both time.
     stop_grace_period: 30s
     env_file: .env
-    environment:
-      WARP_AIO_EMBEDDED_POSTGRES: "true"
-      WARP_DB_DRIVER: postgres
-      WARP_DB_CONNECTION_STRING: postgres:///warp?host=/run/postgresql&user=warp&sslmode=disable
     volumes:
       - warp-data:/data
     ports: