[chore] flake.lock: update inputs

Flake lock file updates:

• Updated input 'nixpkgs':
    'github:NixOS/nixpkgs/1719f27dd95fd4206afb9cec9f415b539978827e' (2024-09-30)
  → 'github:NixOS/nixpkgs/5966581aa04be7eff830b9e1457d56dc70a0b798' (2024-10-02)
• Updated input 'nixvim':
    'github:nix-community/nixvim/5f4a4b47597d3b9ac26c41ff4e8da28fa662f200' (2024-09-29)
  → 'github:nix-community/nixvim/0ca98d02104f7f0a703787a7a080a570b7f1bedd' (2024-10-02)
• Updated input 'nixvim/flake-parts':
    'github:hercules-ci/flake-parts/bcef6817a8b2aa20a5a6dbb19b43e63c5bf8619a' (2024-09-12)
  → 'github:hercules-ci/flake-parts/3d04084d54bedc3d6b8b736c70ef449225c361b1' (2024-10-01)
• Updated input 'unstable':
    'github:NixOS/nixpkgs/06cf0e1da4208d3766d898b7fdab6513366d45b9' (2024-09-29)
  → 'github:NixOS/nixpkgs/27e30d177e57d912d614c88c622dcfdb2e6e6515' (2024-10-01)

flake.lock

@@ -261,11 +261,11 @@
     },
     "nixpkgs": {
       "locked": {
-        "lastModified": 1727672256,
-        "narHash": "sha256-9/79hjQc9+xyH+QxeMcRsA6hDyw6Z9Eo1/oxjvwirLk=",
+        "lastModified": 1727907660,
+        "narHash": "sha256-QftbyPoieM5M50WKUMzQmWtBWib/ZJbHo7mhj5riQec=",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "1719f27dd95fd4206afb9cec9f415b539978827e",
+        "rev": "5966581aa04be7eff830b9e1457d56dc70a0b798",
         "type": "github"
       },
       "original": {