fix: address issues in model pull and chat API

- Refactored model pull logic to improve error handling and user feedback.
- Enhanced chat API to ensure better performance and reliability during message fetching.
- Updated UI components for a more intuitive user experience when interacting with models and messages.

hooks/use-system-monitor.ts

@@ -0,0 +1,29 @@
+import { useState, useEffect } from 'react';
+import { invoke } from '@tauri-apps/api/core';
+import { listen } from '@tauri-apps/api/event';
+
+export interface SystemStats {
+  cpu_usage: number;
+  memory_used: number;
+  memory_total: number;
+}
+
+export function useSystemMonitor() {
+  const [stats, setStats] = useState<SystemStats | null>(null);
+
+  useEffect(() => {
+    // Start the monitor thread in backend
+    invoke('start_system_monitor');
+
+    const unlisten = listen<SystemStats>('system-stats', (event) => {
+      setStats(event.payload);
+    });
+
+    return () => {
+      unlisten.then(f => f());
+    };
+  }, []);
+
+  return stats;
+}
+