Refactor profile screen and organize project structure

- Extract ProfileScreen and components to features/profile
- Move shared hooks and stores to top-level
- Add RLS policies for admin permissions
- Add RELEASING.md guide
- Update .gitignore

apps/supabase/migrations/20260101113000_add_feedback_permission_rls.sql

@@ -0,0 +1,9 @@
+-- Add RLS policies for feedback
+
+CREATE POLICY "Admins with manage_feedback permission can view all feedback"
+  ON feedback FOR SELECT
+  USING (has_permission('manage_feedback'));
+
+CREATE POLICY "Admins with manage_feedback permission can update all feedback"
+  ON feedback FOR UPDATE
+  USING (has_permission('manage_feedback'));