Update flake.lock (#541)

Automated changes by the
[update-flake-lock](https://github.com/DeterminateSystems/update-flake-lock)
GitHub Action.

```
Flake lock file updates:

• Updated input 'devenv':
    'github:cachix/devenv/32c9ecd' (2026-03-09)
  → 'github:cachix/devenv/2105b1a' (2026-03-09)
• Updated input 'fenix':
    'github:nix-community/fenix/fc48638' (2026-03-08)
  → 'github:nix-community/fenix/6ed2afa' (2026-03-09)
• Updated input 'fenix/rust-analyzer-src':
    'github:rust-lang/rust-analyzer/a1b86d6' (2026-03-07)
  → 'github:rust-lang/rust-analyzer/51966da' (2026-03-08)
• Updated input 'home-manager':
    'github:nix-community/home-manager/5be5d82' (2026-03-08)
  → 'github:nix-community/home-manager/bb01474' (2026-03-09)
• Updated input 'nixpkgs':
    'github:NixOS/nixpkgs/aca4d95' (2026-03-06)
  → 'github:NixOS/nixpkgs/9dcb002' (2026-03-08)
• Updated input 'nixpkgs-stable':
    'github:NixOS/nixpkgs/d351a3b' (2026-03-08)
  → 'github:NixOS/nixpkgs/e13b62c' (2026-03-09)
• Updated input 'rust-overlay':
    'github:oxalica/rust-overlay/3c06fdb' (2026-03-09)
  → 'github:oxalica/rust-overlay/1924b46' (2026-03-10)
• Updated input 'sops-nix':
    'github:Mic92/sops-nix/c8e6967' (2026-03-08)
  → 'github:Mic92/sops-nix/d1ff3b1' (2026-03-09)
```

### Running GitHub Actions on this PR

GitHub Actions will not run workflows on pull requests which are opened
by a GitHub Action.

To run GitHub Actions workflows on this PR, run:

```sh
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
```

Author: github-actions[bot]