build(nix): update dependencies

• Updated input 'fenix':
    'github:nix-community/fenix/de681af' (2026-02-09)
  → 'github:nix-community/fenix/b9696f3' (2026-02-17)
• Updated input 'fenix/nixpkgs':
    'github:nixos/nixpkgs/d6c7193' (2026-02-08)
  → 'github:nixos/nixpkgs/a82ccc3' (2026-02-13)
• Updated input 'fenix/rust-analyzer-src':
    'github:rust-lang/rust-analyzer/c75729d' (2026-02-09)
  → 'github:rust-lang/rust-analyzer/3360aeb' (2026-02-16)
• Updated input 'nixlib':
    'github:nix-community/nixpkgs.lib/fd92884' (2026-02-08)
  → 'github:nix-community/nixpkgs.lib/f472c85' (2026-02-15)
• Updated input 'nixpkgs-unstable':
    'github:NixOS/nixpkgs/fef9403' (2026-02-08)
  → 'github:NixOS/nixpkgs/ac055f3' (2026-02-15)

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Author: github-actions[bot]