Module Implementation

This is a standard NixOS-style module that defines options and configuration. For complex modules, you can split this into options.nix and config.nix.

The module should:

1. Define options under stackpanel.modules.<id>.*
2. Define per-app options via appModules if needed
3. Implement config = lib.mkIf cfg.enable { ... }
4. Define flake checks for CI (required for certification)
5. Define health checks for runtime monitoring

For large modules with many checks, consider splitting checks into checks.nix