Add treefmt

Signed-off-by: Nikolaos Karaolidis <nick@karaolidis.com>

treefmt.nix

@@ -0,0 +1,52 @@
+{ ... }:
+{
+  projectRootFile = "flake.nix";
+
+  programs = {
+    nixfmt = {
+      enable = true;
+      strict = true;
+    };
+
+    shellcheck.enable = true;
+    prettier.enable = true;
+    gofmt.enable = true;
+  };
+
+  settings = {
+    global = {
+      excludes = [
+        # Third-party
+        "submodules/*"
+        # Binary Files
+        "*.jpg"
+        "*.png"
+        "*.svg"
+        # Machine-generated
+        "*/secrets.yaml"
+        "*/secrets/*.pub"
+        # Theme Templates
+        "*/theme.css"
+        "*/theme.conf"
+        "*/theme.theme"
+        "*/theme.sass"
+        "*/*.kvconfig"
+        # Git
+        "*/.gitignore"
+        ".gitattributes"
+        ".envrc"
+        # One-offs
+        "hosts/*/users/*/uid"
+        "*/.stignore"
+        "*/spicetify/config/prefs*"
+        "*.zsh"
+        # Manifest Files
+        "*/package.json"
+        "*/go.mod"
+        "*/bun.lockb"
+        # Broken formatters
+        "*.lua"
+      ];
+    };
+  };
+}