flake.lock: Update

Flake lock file updates:

• Updated input 'flake-parts':
    'github:hercules-ci/flake-parts/3107b77cd68437b9a76194f0f7f9c55f2329ca5b?narHash=sha256-91qqW8lhL7TLwgQWijoGBbiD4t7/q75KTi8NxjVmSmA%3D' (2026-04-01)
  → 'github:hercules-ci/flake-parts/5250617bffd85403b14dbf43c3870e7f255d2c16?narHash=sha256-EPIFsulyon7Z1vLQq5Fk64GR8L7cQsT%2BIPhcsukVbgk%3D' (2026-05-01)
• Updated input 'nixpkgs':
    'github:NixOS/nixpkgs/4c1018dae018162ec878d42fec712642d214fdfa?narHash=sha256-ar3rofg%2BawPB8QXDaFJhJ2jJhu%2BKqN/PRCXeyuXR76E%3D' (2026-04-09)
  → 'github:NixOS/nixpkgs/15f4ee454b1dce334612fa6843b3e05cf546efab?narHash=sha256-Ad49moKWeXtKBJNy2ebiTQUEgdLyvGmTeykAQ9xM%2BZ4%3D' (2026-04-30)
• Updated input 'pyproject-build-systems':
    'github:pyproject-nix/build-system-pkgs/b6e74f433b02fa4b8a7965ee24680f4867e2926f?narHash=sha256-ZoTdqZP03DcdoyxvpFHCAek4bkPUTUPUF3oCCgc3dP4%3D' (2026-03-18)
  → 'github:pyproject-nix/build-system-pkgs/ffaa2161dd5d63e0e94591f86b54fc239660fb2e?narHash=sha256-qapCOQmR%2B%2ByZSY43dzrp3wCrkOTLpod%2BONtJWBk6iKU%3D' (2026-04-20)
• Updated input 'pyproject-nix':
    'github:pyproject-nix/pyproject.nix/fb6b728260f3f32761367e9fd1e1a25b4245bcd0?narHash=sha256-NHY9SJNU019n%2B8NCabBDtmuzRFeE2gZlYKHowp9bV24%3D' (2026-04-06)
  → 'github:pyproject-nix/pyproject.nix/69f57f27e52a87c54e28138a75ec741cd46663c9?narHash=sha256-Gs1VnEkCkkRZxJQAC/Dhz0Jbfi22mFXChbtNg9w/Ybg%3D' (2026-04-20)
• Updated input 'uv2nix':
    'github:pyproject-nix/uv2nix/5707df99097375896a3dda811d492a2fabe63500?narHash=sha256-BTb4sydzX2B5/oNbvCdQFeSbk97xEnbb8bk84CiKCOs%3D' (2026-04-09)
  → 'github:pyproject-nix/uv2nix/6c53dcf4d3f63240f57e0b0c826cb15eda61f249?narHash=sha256-1PcD0%2BIZPQXyvmXJ1OYH%2B23sRc9IyOKrUUBYZonVBm8%3D' (2026-04-29)

Author: tfc