build(nix): update dependencies

• Updated input 'fenix':
    'github:nix-community/fenix/6399553' (2025-12-11)
  → 'github:nix-community/fenix/a3eaf68' (2026-01-01)
• Updated input 'fenix/nixpkgs':
    'github:nixos/nixpkgs/addf7cf' (2025-12-08)
  → 'github:nixos/nixpkgs/c0b0e0f' (2025-12-28)
• Updated input 'fenix/rust-analyzer-src':
    'github:rust-lang/rust-analyzer/fface27' (2025-12-10)
  → 'github:rust-lang/rust-analyzer/a9026e6' (2025-12-31)
• Updated input 'nixify':
    'github:rvolosatovs/nixify/47f0350' (2025-12-09)
  → 'github:rvolosatovs/nixify/66ce96c' (2025-12-19)
• Updated input 'nixify/advisory-db':
    'github:rustsec/advisory-db/6b4a28c' (2025-12-08)
  → 'github:rustsec/advisory-db/b3afca3' (2025-12-18)
• Updated input 'nixify/nixpkgs-darwin':
    'github:nixos/nixpkgs/9393af3' (2025-12-07)
  → 'github:nixos/nixpkgs/bc80944' (2025-12-17)
• Updated input 'nixify/nixpkgs-nixos':
    'github:nixos/nixpkgs/00d2457' (2025-12-05)
  → 'github:nixos/nixpkgs/2b0d2b4' (2025-12-17)
• Updated input 'nixify/rust-overlay':
    'github:oxalica/rust-overlay/7ed7e8c' (2025-12-08)
  → 'github:oxalica/rust-overlay/96617c9' (2025-12-18)
• Updated input 'nixlib':
    'github:nix-community/nixpkgs.lib/2075416' (2025-12-14)
  → 'github:nix-community/nixpkgs.lib/15177f8' (2025-12-28)
• Updated input 'nixpkgs-unstable':
    'github:NixOS/nixpkgs/af84f9d' (2025-12-17)
  → 'github:NixOS/nixpkgs/c04833a' (2026-01-01)

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Author: github-actions[bot]