Common: replace neovim with helix

roles/common/programs/helix.nix

@@ -0,0 +1,22 @@
+{ pkgs, ... }:
+
+{
+  home-manager.users.toast = {
+    programs.helix = {
+      enable = true;
+      defaultEditor = true;
+      settings = {
+        theme = "catppuccin_mocha";
+        editor = {
+          mouse = true;
+          cursorline = true;
+          statusline.mode = {
+            normal = "Normal";
+            insert = "Insert";
+            select = "Select";
+          };
+        };
+      };
+    };
+  };
+}