flake.lock: Update

Flake lock file updates:

• Updated input 'hercules-ci-effects':
    'github:hercules-ci/hercules-ci-effects/524637ef84c177661690b924bf64a1ce18072a2c?narHash=sha256-I6fG1zrfdLFcp/imGZElig0BJO3YU0QEXLgvwWoOpJ8%3D' (2025-03-15)
  → 'github:hercules-ci/hercules-ci-effects/5b6cec51c9ec095a0d3fd4c8eeb53eb5c59ae33e?narHash=sha256-1Z4WPGVky4w3lrhrgs89OKsLzPdtkbi1bPLNFWsoLfY%3D' (2025-04-15)
• Updated input 'nixpkgs':
    'git+https://github.com/NixOS/nixpkgs?ref=nixos-unstable-small&rev=208645bf60302e4eea10f9b038043205b423de21&shallow=1' (2025-04-12)
  → 'git+https://github.com/NixOS/nixpkgs?ref=nixos-unstable-small&rev=ae0c0ebf757121ee44bb98e70a71212a9961055d&shallow=1' (2025-04-19)
• Updated input 'treefmt-nix':
    'github:numtide/treefmt-nix/815e4121d6a5d504c0f96e5be2dd7f871e4fd99d?narHash=sha256-uhjnlaVTWo5iD3LXics1rp9gaKgDRQj6660%2BgbUU3cE%3D' (2025-04-04)
  → 'github:numtide/treefmt-nix/8d404a69efe76146368885110f29a2ca3700bee6?narHash=sha256-aRmUh0AMwcbdjJHnytg1e5h5ECcaWtIFQa6d9gI85AI%3D' (2025-04-18)

Author: github-actions[bot]