refactor: switch formatter from nixpkgs-fmt to alejandra

AGENTS.md

@@ -37,7 +37,7 @@ Personal Nix flake: custom packages, overlays, NixOS/Home Manager modules, dev s
 
 ## CONVENTIONS
 
-**Formatter**: `nix fmt` before commit (nixpkgs-fmt)
+**Formatter**: `nix fmt` before commit (alejandra)
 
 **Naming**:
 - Packages: `lowercase-hyphen` (e.g., `hyprpaper-random`)
@@ -105,7 +105,7 @@ Generated: `/etc/m3ta/ports.json` (NixOS), `~/.config/m3ta/ports.json` (HM)
 
 ```bash
 nix flake check              # Validate flake
-nix fmt                      # Format (nixpkgs-fmt)
+nix fmt                      # Format (alejandra)
 nix build .#<pkg>            # Build package
 nix flake show               # List outputs
 nix develop                  # Enter dev shell

flake.nix

@@ -89,7 +89,7 @@
     # Formatter for 'nix fmt'
     formatter = forAllSystems (
       system:
-        (pkgsFor system).nixpkgs-fmt
+        (pkgsFor system).alejandra
     );
 
     # Templates for creating new packages/modules

shells/default.nix

@@ -8,7 +8,7 @@
 
     buildInputs = with pkgs; [
       nil # Nix LSP
-      nixpkgs-fmt # Nix formatter
+      alejandra # Nix formatter
       nix-tree # Explore dependency trees
       statix # Nix linter
       deadnix # Find dead Nix code
@@ -20,7 +20,7 @@
       echo "  nix flake check    - Check flake validity"
       echo "  nix flake show     - Show flake outputs"
       echo "  nix build .#<pkg>  - Build a package"
-      echo "  nixpkgs-fmt .      - Format Nix files"
+      echo "  nix fmt .           - Format Nix files"
       echo "  statix check .     - Lint Nix files"
       echo "  deadnix .          - Find dead code"
     '';