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-compose.quickstart.yml

@@ -1,18 +0,0 @@
-services:
-  paperclip:
-    build:
-      context: .
-      dockerfile: Dockerfile
-    ports:
-      - "${PAPERCLIP_PORT:-3100}:3100"
-    environment:
-      HOST: "0.0.0.0"
-      PAPERCLIP_HOME: "/paperclip"
-      OPENAI_API_KEY: "${OPENAI_API_KEY:-}"
-      ANTHROPIC_API_KEY: "${ANTHROPIC_API_KEY:-}"
-      PAPERCLIP_DEPLOYMENT_MODE: "authenticated"
-      PAPERCLIP_DEPLOYMENT_EXPOSURE: "private"
-      PAPERCLIP_PUBLIC_URL: "${PAPERCLIP_PUBLIC_URL:-http://localhost:3100}"
-      BETTER_AUTH_SECRET: "${BETTER_AUTH_SECRET:?BETTER_AUTH_SECRET must be set}"
-    volumes:
-      - "${PAPERCLIP_DATA_DIR:-./data/docker-paperclip}:/paperclip"