Implement API improvements Phases 1-4

src/docs/API_PATTERNS.md

@@ -306,6 +306,41 @@ When migrating a component:
   - Features: Automatic caching, refetch on window focus, 5-minute stale time
   - Returns: Array of blocked users with profile information
 
+### Security
+- **`useEmailChangeStatus`** - Query email change verification status
+  - Queries: `get_email_change_status` RPC function
+  - Features: Automatic polling every 30 seconds, 15-second stale time
+  - Returns: Email change status with verification flags
+
+- **`useSessions`** - Fetch active user sessions
+  - Queries: `get_my_sessions` RPC function
+  - Features: Automatic caching, refetch on window focus, 5-minute stale time
+  - Returns: Array of active sessions with device info
+
+---
+
+## Type Safety Guidelines
+
+Always use proper TypeScript types in hooks:
+
+```typescript
+// ✅ CORRECT - Define proper interfaces
+interface Profile {
+  display_name?: string;
+  bio?: string;
+}
+
+queryClient.setQueryData<Profile>(['profile', userId], (old) => 
+  old ? { ...old, ...updates } : old
+);
+
+// ❌ WRONG - Using any type
+queryClient.setQueryData(['profile', userId], (old: any) => ({
+  ...old,
+  ...updates
+}));
+```
+
 ---
 
 ## Cache Invalidation Guidelines