fix: remove build sections from docker-compose.yml so pull works

docker compose pull was skipping with "No image to be pulled" because
the build: sections made Compose treat local builds as authoritative.
Moved build config to docker-compose.build.yml for developers.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

docker-compose.build.yml

@@ -0,0 +1,11 @@
+# Developer override — build images from source instead of pulling from GHCR.
+# Usage: docker compose -f docker-compose.yml -f docker-compose.build.yml build
+services:
+  backend:
+    build:
+      context: .
+      dockerfile: ./backend/Dockerfile
+
+  frontend:
+    build:
+      context: ./frontend

docker-compose.yml

@@ -1,9 +1,6 @@
 services:
   backend:
     image: ghcr.io/bigbodycobain/shadowbroker-backend:latest
-    build:
-      context: .
-      dockerfile: ./backend/Dockerfile
     container_name: shadowbroker-backend
     ports:
       - "${BIND:-127.0.0.1}:8000:8000"
@@ -32,8 +29,6 @@ services:
 
   frontend:
     image: ghcr.io/bigbodycobain/shadowbroker-frontend:latest
-    build:
-      context: ./frontend
     container_name: shadowbroker-frontend
     ports:
       - "${BIND:-127.0.0.1}:3000:3000"