chore(docker): restore the dev postgres pg_partman image

An earlier change on this branch inadvertently reverted the dev postgres setup
back to plain postgres:14, dropping the pg_partman build and its
shared_preload_libraries that were added separately on main. Restore
docker-compose.yml, dev-compose.yml, and Dockerfile.postgres to match main so
merging this branch does not undo that.

Author: ericallam

docker/Dockerfile.postgres

@@ -0,0 +1,5 @@
+FROM postgres:14
+
+RUN apt-get update \
+    && apt-get install -y --no-install-recommends postgresql-14-partman \
+    && rm -rf /var/lib/apt/lists/*

docker/dev-compose.yml

@@ -12,7 +12,9 @@ networks:
 services:
   db:
     container_name: db-dev
-    image: postgres:14
+    build:
+      context: .
+      dockerfile: Dockerfile.postgres
     restart: always
     volumes:
       - database-data:/var/lib/postgresql/data/
@@ -29,6 +31,8 @@ services:
       - listen_addresses=*
       - -c
       - wal_level=logical
+      - -c
+      - shared_preload_libraries=pg_partman_bgw
 
   electric:
     container_name: electric-dev

docker/docker-compose.yml

@@ -25,7 +25,9 @@ networks:
 services:
   database:
     container_name: ${CONTAINER_PREFIX:-}database
-    image: postgres:14
+    build:
+      context: .
+      dockerfile: Dockerfile.postgres
     restart: always
     volumes:
       - ${DB_VOLUME:-database-data}:/var/lib/postgresql/data/
@@ -42,6 +44,8 @@ services:
       - listen_addresses=*
       - -c
       - wal_level=logical
+      - -c
+      - shared_preload_libraries=pg_partman_bgw
       # The webapp opens ~50 pooled connections per instance and Electric another
       # ~40, so the default 100 is exhausted by one webapp + Electric alone. Raise
       # it so multiple instances / load tests have headroom.
@@ -90,7 +94,9 @@ services:
   database-replica:
     container_name: ${CONTAINER_PREFIX:-}database-replica
     profiles: ["replica"]
-    image: postgres:14
+    build:
+      context: .
+      dockerfile: Dockerfile.postgres
     restart: always
     depends_on:
       - database