deps: update flake.lock (#135)

Flake lock file updates:

• Updated input 'nixpkgs':
    'github:nixos/nixpkgs/00b574b1ba8a352f0601c4dde4faff4b534ebb1e?narHash=sha256-WrZ280bT6NzNbBo%2BCKeJA/NW1rhvN/RUPZczqCpu2mI%3D' (2025-08-09)
  → 'github:nixos/nixpkgs/32f313e49e42f715491e1ea7b306a87c16fe0388?narHash=sha256-nNaeJjo861wFR0tjHDyCnHs1rbRtrMgxAKMoig9Sj/w%3D' (2025-08-15)

Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>

Author: mrcjkb