feat: update flake.lock (#98)

Flake lock file updates:

• Updated input 'nixpkgs':
    'github:nixos/nixpkgs/d7600c775f877cd87b4f5a831c28aa94137377aa?narHash=sha256-tlOn88coG5fzdyqz6R93SQL5Gpq%2Bm/DsWpekNFhqPQk%3D' (2025-08-30)
  → 'github:nixos/nixpkgs/8eb28adfa3dc4de28e792e3bf49fcf9007ca8ac9?narHash=sha256-NOrUtIhTkIIumj1E/Rsv1J37Yi3xGStISEo8tZm3KW4%3D' (2025-09-05)

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Author: github-actions[bot]