feat: Implement Phase 2, 3, 4 - Module Settings System with Schema Forms and Addon API

Phase 2: Schema-Based Form System
- Add ModuleSettingsController with GET/POST/schema endpoints
- Create SchemaField component supporting 8 field types (text, textarea, email, url, number, toggle, checkbox, select)
- Create SchemaForm component for automatic form generation from schema
- Add ModuleSettings page with dynamic routing (/settings/modules/:moduleId)
- Add useModuleSettings React hook for settings management
- Implement NewsletterSettings as example with 8 configurable fields
- Add has_settings flag to module registry
- Settings stored as woonoow_module_{module_id}_settings

Phase 3: Advanced Features
- Create windowAPI.ts exposing React, hooks, components, icons, utils to addons via window.WooNooW
- Add DynamicComponentLoader for loading external React components
- Create TypeScript definitions (woonoow-addon.d.ts) for addon developers
- Initialize Window API in App.tsx on mount
- Enable custom React components for addon settings pages

Phase 4: Production Polish & Example
- Create complete Biteship addon example demonstrating both approaches:
  * Schema-based settings (no build required)
  * Custom React component (with build)
- Add comprehensive README with installation and testing guide
- Include package.json with esbuild configuration
- Demonstrate window.WooNooW API usage in custom component

Bug Fixes:
- Fix footer newsletter form visibility (remove redundant module check)
- Fix footer contact_data and social_links not saving (parameter name mismatch: snake_case vs camelCase)
- Fix useModules hook returning undefined (remove .data wrapper, add fallback)
- Add optional chaining to footer settings rendering
- Fix TypeScript errors in woonoow-addon.d.ts (use any for external types)

Files Added (15):
- includes/Api/ModuleSettingsController.php
- includes/Modules/NewsletterSettings.php
- admin-spa/src/components/forms/SchemaField.tsx
- admin-spa/src/components/forms/SchemaForm.tsx
- admin-spa/src/routes/Settings/ModuleSettings.tsx
- admin-spa/src/hooks/useModuleSettings.ts
- admin-spa/src/lib/windowAPI.ts
- admin-spa/src/components/DynamicComponentLoader.tsx
- types/woonoow-addon.d.ts
- examples/biteship-addon/biteship-addon.php
- examples/biteship-addon/src/Settings.jsx
- examples/biteship-addon/package.json
- examples/biteship-addon/README.md
- PHASE_2_3_4_SUMMARY.md

Files Modified (11):
- admin-spa/src/App.tsx
- admin-spa/src/hooks/useModules.ts
- admin-spa/src/routes/Appearance/Footer.tsx
- admin-spa/src/routes/Settings/Modules.tsx
- customer-spa/src/hooks/useModules.ts
- customer-spa/src/layouts/BaseLayout.tsx
- customer-spa/src/components/NewsletterForm.tsx
- includes/Api/Routes.php
- includes/Api/ModulesController.php
- includes/Core/ModuleRegistry.php
- woonoow.php

API Endpoints Added:
- GET /woonoow/v1/modules/{module_id}/settings
- POST /woonoow/v1/modules/{module_id}/settings
- GET /woonoow/v1/modules/{module_id}/schema

For Addon Developers:
- Schema-based: Define settings via woonoow/module_settings_schema filter
- Custom React: Build component using window.WooNooW API, externalize react/react-dom
- Both approaches use same storage and retrieval methods
- TypeScript definitions provided for type safety
- Complete working example (Biteship) included

admin-spa/src/App.tsx

@@ -44,6 +44,7 @@ import { useActiveSection } from '@/hooks/useActiveSection';
 import { NAV_TREE_VERSION } from '@/nav/tree';
 import { __ } from '@/lib/i18n';
 import { ThemeToggle } from '@/components/ThemeToggle';
+import { initializeWindowAPI } from '@/lib/windowAPI';
 
 function useFullscreen() {
   const [on, setOn] = useState<boolean>(() => {
@@ -239,6 +240,7 @@ import EmailCustomization from '@/routes/Settings/Notifications/EmailCustomizati
 import EditTemplate from '@/routes/Settings/Notifications/EditTemplate';
 import SettingsDeveloper from '@/routes/Settings/Developer';
 import SettingsModules from '@/routes/Settings/Modules';
+import ModuleSettings from '@/routes/Settings/ModuleSettings';
 import AppearanceIndex from '@/routes/Appearance';
 import AppearanceGeneral from '@/routes/Appearance/General';
 import AppearanceHeader from '@/routes/Appearance/Header';
@@ -553,6 +555,7 @@ function AppRoutes() {
       <Route path="/settings/brand" element={<SettingsIndex />} />
       <Route path="/settings/developer" element={<SettingsDeveloper />} />
       <Route path="/settings/modules" element={<SettingsModules />} />
+      <Route path="/settings/modules/:moduleId" element={<ModuleSettings />} />
       
       {/* Appearance */}
       <Route path="/appearance" element={<AppearanceIndex />} />
@@ -729,6 +732,11 @@ function AuthWrapper() {
 }
 
 export default function App() {
+  // Initialize Window API for addon developers
+  React.useEffect(() => {
+    initializeWindowAPI();
+  }, []);
+  
   return (
     <QueryClientProvider client={qc}>
       <HashRouter>