feat: implement cache layer, CSP improvements, and database performance optimizations

- Add Redis cache implementation with LRU eviction
- Enhance Content Security Policy with nonce generation
- Optimize database queries with connection pooling
- Add cache invalidation API endpoints
- Improve security monitoring performance

lib/hooks/useCSRF.ts

@@ -7,7 +7,7 @@
 "use client";
 
 import { useCallback, useEffect, useState } from "react";
-import { CSRFClient } from "../csrf";
+import { CSRFClient } from "../csrf-client";
 
 /**
  * Hook for managing CSRF tokens