Add Linker and Optimizer modules with API integration and frontend components

- Added Linker and Optimizer apps to `INSTALLED_APPS` in `settings.py`.
- Configured API endpoints for Linker and Optimizer in `urls.py`.
- Implemented `OptimizeContentFunction` for content optimization in the AI module.
- Created prompts for content optimization and site structure generation.
- Updated `OptimizerService` to utilize the new AI function for content optimization.
- Developed frontend components including dashboards and content lists for Linker and Optimizer.
- Integrated new routes and sidebar navigation for Linker and Optimizer in the frontend.
- Enhanced content management with source and sync status filters in the Writer module.
- Comprehensive test coverage added for new features and components.

frontend/src/api/linker.api.ts

@@ -0,0 +1,32 @@
+import { fetchAPI } from '../services/api';
+
+/**
+ * Linker API Client
+ * Functions for internal linking operations
+ */
+export const linkerApi = {
+  /**
+   * Process a single content item for internal linking
+   * @param contentId - Content ID to process
+   * @returns Link result with links added
+   */
+  process: async (contentId: number) => {
+    return await fetchAPI('/v1/linker/process/', {
+      method: 'POST',
+      body: JSON.stringify({ content_id: contentId }),
+    });
+  },
+
+  /**
+   * Batch process multiple content items for internal linking
+   * @param contentIds - Array of content IDs to process
+   * @returns Array of link results
+   */
+  batchProcess: async (contentIds: number[]) => {
+    return await fetchAPI('/v1/linker/batch_process/', {
+      method: 'POST',
+      body: JSON.stringify({ content_ids: contentIds }),
+    });
+  },
+};
+