flake.lock: Update

Flake lock file updates:

• Updated input 'flake-parts':
    'github:hercules-ci/flake-parts/c621e8422220273271f52058f618c94e405bb0f5?narHash=sha256-hIshGgKZCgWh6AYJpJmRgFdR3WUbkY04o82X05xqQiY%3D' (2025-04-01)
  → 'github:hercules-ci/flake-parts/49f0870db23e8c1ca0b5259734a02cd9e1e371a1?narHash=sha256-F82%2BgS044J1APL0n4hH50GYdPRv/5JWm34oCJYmVKdE%3D' (2025-06-01)
• Updated input 'nixpkgs':
    'git+https://github.com/NixOS/nixpkgs?ref=nixos-unstable-small&rev=c3ee76c437067f1ae09d6e530df46a3f80977992&shallow=1' (2025-05-24)
  → 'git+https://github.com/NixOS/nixpkgs?ref=nixos-unstable-small&rev=a1ba3c5c21b2424ad0bd13bbbfa50ebfbd54823e&shallow=1' (2025-06-04)
• Updated input 'treefmt-nix':
    'github:numtide/treefmt-nix/020cb423808365fa3f10ff4cb8c0a25df35065a3?narHash=sha256-XgxghfND8TDypxsMTPU2GQdtBEsHTEc3qWE6RVEk8O0%3D' (2025-05-22)
  → 'github:numtide/treefmt-nix/1f3f7b784643d488ba4bf315638b2b0a4c5fb007?narHash=sha256-9YzfeN8CB6SzNPyPm2XjRRqSixDopTapaRsnTpXUEY8%3D' (2025-05-26)

Author: github-actions[bot]