flake.lock: Update

Flake lock file updates:

• Updated input 'fenix':
    'github:nix-community/fenix/933bc78d45abaf764dbfe0fd117be981631f3e9a?narHash=sha256-79O83W9osY3wyvxZHqL0gw85tcACSX0TU5en3%2Bdky/0%3D' (2025-06-21)
  → 'github:nix-community/fenix/e60617a7e9ad348c2679557d01177f9d244e6e5d?narHash=sha256-OoD7QdCBKk41sjGr7UpTxXtVba2kc2gfdex2qUCO1FQ%3D' (2025-07-04)
• Updated input 'fenix/rust-analyzer-src':
    'github:rust-lang/rust-analyzer/b0552d779f7137c76f109666ce0ad28395c0e582?narHash=sha256-EMFKnO%2BJ3dZOa9J%2BuiKZgHYgzALv9dqxY7NHV0DbO/U%3D' (2025-06-20)
  → 'github:rust-lang/rust-analyzer/040049b79973a742bbd0eef25369b983f764dc38?narHash=sha256-X%2BeVYBgJtR5WtFGifchtuidsl0epV3%2BoKXVxdd9ntuY%3D' (2025-07-03)
• Updated input 'nixpkgs':
    'github:NixOS/nixpkgs/076e8c6678d8c54204abcb4b1b14c366835a58bb?narHash=sha256-1ovgdmuDYVo5OUC5NzdF%2BV4zx2uT8RtsgZahxidBTyw%3D' (2025-06-20)
  → 'github:NixOS/nixpkgs/c860cf0b3a0829f0f6cf344ca8de83a2bbfab428?narHash=sha256-4E7wWftF1ExK5ZEDzj41%2B9mVgxtuRV3wWCId7QAYMAU%3D' (2025-07-04)

Author: github-actions[bot]