Wraps openssl rand -hex 32 (with /dev/urandom fallback) so operators don't
have to remember the incantation. Defaults to printing the secret;
--write [path] sets/replaces CM_AUTH_SECRET in the target .env (./.env by
default) and prints the restart command.
- move Python sources into app package and switch services to module entrypoints
- relocate Dockerfiles under docker/, add buildx publish script, override compose for local builds
- configure images to pull from gitea.04080616.xyz/yiekheng with env-driven tags and limits
- harden installs and transfer worker logging/concurrency for cleaner container output
