Nix Flake Warning: Use of deprecated xorg package and lack of app metadata

[YuriNek0]

Issues

nix flake check --no-build reports:

• app lacks meta.description
  Some nixpkgs revisions deprecate/reshape pkgs.xorg.* usage patterns, causing warnings or breakage over time.

Also metadata currently has inconsistencies:

• license mismatch with project docs
• maintainer format not following nix conventions

Proposal

• Add meta.description to apps.default
• Align meta.license with repo license
• Normalize/remove meta.maintainers to valid nix style

Resolve X11 libraries through compatibility lookups:

• prefer modern attrs when available
• fallback to pkgs.xorg.* for compatibility