The crawler subdirectory was the only active project. Moving it to the
repo root simplifies paths and removes the unnecessary nesting. The
vqa/ and immoweb/ directories were legacy/unused and have been removed.
Updated .drone.yml, .gitignore, .claude/ docs, and skills to reflect
the new flat structure.
Containerize the frontend dev server (Vite) and add a Caddy reverse
proxy for HTTPS termination, replacing the manual local setup. The
Caddy config proxies /api/* to the backend and everything else to the
frontend dev server.
Also simplify start.sh: remove --local Poetry mode, extract
get_compose_cmd helper, and document new services and DEV_HOST env var.
