feat: Initialize frontend with React, Vite, and Tailwind CSS

- Set up main entry point for React application.
- Create About, Home, NotFound, Privacy, and Terms pages with SEO support.
- Implement API service for file uploads and task management.
- Add global styles using Tailwind CSS.
- Create utility functions for SEO and text processing.
- Configure Vite for development and production builds.
- Set up Nginx configuration for serving frontend and backend.
- Add scripts for cleanup of expired files and sitemap generation.
- Implement deployment script for production environment.

backend/celery_worker.py

@@ -0,0 +1,11 @@
+"""Celery worker entry point."""
+from app import create_app
+from app.extensions import celery
+
+app = create_app()
+
+# Import all tasks so Celery discovers them
+import app.tasks.convert_tasks  # noqa: F401
+import app.tasks.compress_tasks  # noqa: F401
+import app.tasks.image_tasks  # noqa: F401
+import app.tasks.video_tasks  # noqa: F401