flake.lock: Update

Flake lock file updates:

• Updated input 'flake-parts':
    'github:hercules-ci/flake-parts/f20dc5d' (2026-03-01)
  → 'github:hercules-ci/flake-parts/3107b77' (2026-04-01)
• Updated input 'flake-parts/nixpkgs-lib':
    'github:nix-community/nixpkgs.lib/c185c7a' (2026-03-01)
  → 'github:nix-community/nixpkgs.lib/333c4e0' (2026-03-29)
• Updated input 'git-hooks-nix':
    'github:cachix/git-hooks.nix/f799ae9' (2026-03-21)
  → 'github:cachix/git-hooks.nix/4e0eb04' (2026-04-01)
• Updated input 'nixpkgs':
    'github:nixos/nixpkgs/b40629e' (2026-03-18)
  → 'github:nixos/nixpkgs/6201e20' (2026-04-01)

Author: pinguibot