docs: Cursor rule for prototyping

.cursor/rules/prototype.mdc

@@ -0,0 +1,11 @@
+---
+description: Apply when you are explicitly asked to implement a quick prototype.
+globs: 
+---
+# Prototype Guidelines
+
+1. Use `debugPref` in `ui/settings/AboutCategory.java` as your prototype entry point:
+    - For feature testing: Trigger your new code when `debugPref` is clicked
+    - For UI testing: Launch your test view when `debugPref` is clicked
+2. Use `R.drawable.ic_null` instead of creating new drawable assets
+3. Keep changes minimal and prefer adding new code over modifying existing code

app/src/main/java/deltazero/amarok/ui/settings/AboutCategory.java

@@ -76,5 +76,11 @@ public class AboutCategory extends BaseCategory {
         usagePref.setIntent(new Intent(Intent.ACTION_VIEW,
                 Uri.parse(activity.getString(R.string.doc_url))));
         addPreference(usagePref);
+
+        var debugPref = new Preference(activity);
+        debugPref.setTitle(R.string.show_debug_info);
+        debugPref.setIcon(R.drawable.ic_null);
+        debugPref.setSummary(R.string.debug_info_description);
+        addPreference(debugPref);
     }
 }