flake.lock: Update

Flake lock file updates:

• Updated input 'cmpkgs':
    'github:nixos/nixpkgs/5b2c2d8' (2026-03-16)
  → 'github:nixos/nixpkgs/cda4854' (2026-03-17)
• Updated input 'determinate':
    'github:DeterminateSystems/determinate/dc4d71b' (2026-03-05)
  → 'github:DeterminateSystems/determinate/d01fc66' (2026-03-17)
• Updated input 'ghostty':
    'github:ghostty-org/ghostty/c1326c5' (2026-03-16)
  → 'github:ghostty-org/ghostty/c9e1006' (2026-03-18)
• Updated input 'helix':
    'github:helix-editor/helix/e2932b4' (2026-03-16)
  → 'github:helix-editor/helix/510edb5' (2026-03-17)
• Updated input 'home-manager':
    'github:nix-community/home-manager/57d5560' (2026-03-16)
  → 'github:nix-community/home-manager/d47357a' (2026-03-18)
• Updated input 'nixpkgs-unstable':
    'github:nixos/nixpkgs/a07d4ce' (2026-03-15)
  → 'github:nixos/nixpkgs/f8573b9' (2026-03-16)
• Updated input 'sops-nix':
    'github:Mic92/sops-nix/c469b68' (2026-03-15)
  → 'github:Mic92/sops-nix/8237de8' (2026-03-16)

Author: colemickens