fix: add ca-certificates and openssl for SSL connectivity

feat: add python3-venv and screen

feat: install sudo, grant node user passwordless sudo

Update Dockerfile

Update Dockerfile

docs: clarify why machine-id must be baked in at build time

feat: add python3-pip, wget, curl, git, neofetch, mediainfo, yt-dlp

fix: pin machine-id + seed shellular config from env vars to bypass rate limit

fix: use existing node user (UID 1000) instead of useradd

Initial upload: Shellular Web UI + keep-alive service