chore: update flake.lock

[mrcjkb]

Automated changes by the update-flake-lock GitHub Action.

Flake lock file updates:

• Updated input 'nixpkgs':
    'github:NixOS/nixpkgs/3d8f0f3f72a6cd4d93d0ad13203f2ea1cb7e1456?narHash=sha256-q%2BfF42iv/geEbHfgSzy3tS0FF/EyD6XTZ98E6yxiBO8%3D' (2026-05-23)
  → 'github:NixOS/nixpkgs/e9a7635a57597d9754eccebdfc7045e6c8600e6b?narHash=sha256-u6WU/yd/o8iYQrHX3RAwO1hYa3LkoSL%2BWNQD0rJfJZQ%3D' (2026-05-29)

Running GitHub Actions on this PR

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To run GitHub Actions workflows on this PR, run:

git branch -D update_flake_lock_action
git fetch origin
git checkout update_flake_lock_action
git commit --amend --no-edit
git push origin update_flake_lock_action --force