chore(docker): improve base image and organize docker files

- Add wget, ripgrep, python3, and GitHub CLI (gh) to base image
- Add OPENCODE_ALLOW_ALL_MODELS=true to production ENV
- Move compose files, onboard-smoke Dockerfile to docker/
- Move entrypoint script to scripts/docker-entrypoint.sh
- Add Podman Quadlet unit files (pod, app, db containers)
- Add docker/README.md with build, compose, and quadlet docs
- Add scripts/docker-build-test.sh for local build validation
- Update all doc references for new file locations
- Keep main Dockerfile at project root (no .dockerignore changes needed)

Co-Authored-By: Paperclip <noreply@paperclip.ing>

docker/docker-compose.yml

@@ -0,0 +1,40 @@
+services:
+  db:
+    image: postgres:17-alpine
+    environment:
+      POSTGRES_USER: paperclip
+      POSTGRES_PASSWORD: paperclip
+      POSTGRES_DB: paperclip
+    healthcheck:
+      test: ["CMD-SHELL", "pg_isready -U paperclip -d paperclip"]
+      interval: 2s
+      timeout: 5s
+      retries: 30
+    ports:
+      - "5432:5432"
+    volumes:
+      - pgdata:/var/lib/postgresql/data
+
+  server:
+    build:
+      context: ..
+      dockerfile: Dockerfile
+    ports:
+      - "3100:3100"
+    environment:
+      DATABASE_URL: postgres://paperclip:paperclip@db:5432/paperclip
+      PORT: "3100"
+      SERVE_UI: "true"
+      PAPERCLIP_DEPLOYMENT_MODE: "authenticated"
+      PAPERCLIP_DEPLOYMENT_EXPOSURE: "private"
+      PAPERCLIP_PUBLIC_URL: "${PAPERCLIP_PUBLIC_URL:-http://localhost:3100}"
+      BETTER_AUTH_SECRET: "${BETTER_AUTH_SECRET:?BETTER_AUTH_SECRET must be set}"
+    volumes:
+      - paperclip-data:/paperclip
+    depends_on:
+      db:
+        condition: service_healthy
+
+volumes:
+  pgdata:
+  paperclip-data: