fix: update timer types to NodeJS.Timeout for better type safety

Author: Le-Caignec

src/components/CLIDemo.vue

@@ -217,8 +217,8 @@ const terminalContent = ref<HTMLElement | null>(null);
 const typedAnswers = ref<Record<number, string>>({});
 
 // Timers
-let animationTimer: number | null = null;
-let typingTimer: number | null = null;
+let animationTimer: NodeJS.Timeout | null = null;
+let typingTimer: NodeJS.Timeout | null = null;
 
 // Typing animation
 const typeText = (text: string, stepIndex: number, onComplete?: () => void) => {