feat: Complete Smart Resume Formatter with R2 and Gemini AI integration

- Integrated Cloudflare R2 for template storage and converted file management
- Added Google Gemini AI for resume parsing and HTML generation
- Created backend API endpoints for templates, conversion, and history
- Refactored frontend to use real API instead of mock data
- Fixed Docker networking issues (IPv6/IPv4) for R2 connectivity
- Added resumeService.ts for frontend API integration
- Updated Vite configuration for proper asset serving in Docker
- Successfully tested with 13 templates from R2 bucket

frontend/components/FilePreviewModal.tsx

@@ -0,0 +1,43 @@
+
+import React from 'react';
+import { X } from 'lucide-react';
+
+interface FilePreviewModalProps {
+  url: string | null;
+  onClose: () => void;
+}
+
+const FilePreviewModal: React.FC<FilePreviewModalProps> = ({ url, onClose }) => {
+  if (!url) return null;
+
+  return (
+    <div 
+      className="fixed inset-0 bg-black bg-opacity-60 flex justify-center items-center z-50 p-4"
+      onClick={onClose}
+    >
+      <div 
+        className="bg-white dark:bg-slate-800 rounded-lg shadow-2xl w-full max-w-4xl h-full max-h-[90vh] flex flex-col overflow-hidden"
+        onClick={(e) => e.stopPropagation()}
+      >
+        <div className="flex justify-between items-center p-4 border-b border-slate-200 dark:border-slate-700">
+          <h2 className="text-lg font-semibold text-slate-800 dark:text-slate-200">File Preview</h2>
+          <button 
+            onClick={onClose} 
+            className="p-1 rounded-full text-slate-500 hover:bg-slate-200 dark:hover:bg-slate-700 transition-colors"
+          >
+            <X className="w-6 h-6" />
+          </button>
+        </div>
+        <div className="flex-grow">
+          <iframe
+            src={url}
+            title="File Preview"
+            className="w-full h-full border-0"
+          />
+        </div>
+      </div>
+    </div>
+  );
+};
+
+export default FilePreviewModal;