v0.0.2: Add env defaults and README run examples

Introduce default environment variables in the Dockerfile (SERVER_NAME, AUTOMATIC_HTTPS, PHP_OPCACHE_ENABLE, APP_BASE_URL, STORAGE_DSN, CACHE_DIR, LISTING_TTL_SECONDS, AUTH_USER) to provide sensible container defaults. Update README with a minimal docker run example (only AUTH_PASS required) and set the default APP_BASE_URL to http://localhost:8080 so generated dist links resolve correctly.