flake.lock: Update (#506)

Flake lock file updates:

• Updated input 'neovim-nightly':
    'github:nix-community/neovim-nightly-overlay/9def1919ea4ca5c16022845ccd57060bd22b6ff5?narHash=sha256-Zzs8LEZhYAGQkcYc8rvvyinE7KqMEtzb9X8Lkja1Y8E%3D' (2025-02-28)
  → 'github:nix-community/neovim-nightly-overlay/06c050aa63007593fec78c38d37f75e28fe3f740?narHash=sha256-hF7yeQ%2BljZeHdybfemarAVjABCWb5SUtWgyhEgIzUVc%3D' (2025-03-01)
• Updated input 'neovim-nightly/neovim-src':
    'github:neovim/neovim/3eee6f9d631b6c220564ef792c542964ed5e1cb9?narHash=sha256-Cj0l7WAMnI%2BEImtKqE0r4Aj14vZOBcTk8pnbBbUPsSY%3D' (2025-02-27)
  → 'github:neovim/neovim/45d7aa3301d436aef3cf5d88db8d0da145f9b70c?narHash=sha256-yY6ipjD1eMUtOK69ZrBH3JCxrmKlLAxWf%2BDgYUpqwgE%3D' (2025-02-28)

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