code-review-fix task 12.7: add hasLoaded flag to TalibPatternPanel to prevent re-fetch on empty array

src/components/TalibPatternPanel.tsx

@@ -1,6 +1,6 @@
 'use client';
 
-import { useState, useEffect, useCallback } from 'react';
+import { useState, useEffect, useCallback, useRef } from 'react';
 import { ChevronDown, Trash2 } from 'lucide-react';
 
 interface PatternInfo {
@@ -33,21 +33,23 @@ export default function TalibPatternPanel({
   const [results, setResults] = useState<DetectionResult[]>([]);
   const [deletingLabel, setDeletingLabel] = useState<string | null>(null);
   const [isDeletingAll, setIsDeletingAll] = useState(false);
+  const hasLoaded = useRef(false);
 
   // Fetch available patterns when panel expands
   useEffect(() => {
-    if (expanded && patterns.length === 0) {
+    if (expanded && !hasLoaded.current) {
       setIsFetchingPatterns(true);
       fetch('/api/patterns/available')
         .then((r) => r.json())
         .then((data) => {
           const list: PatternInfo[] = data.patterns || data;
           setPatterns(list);
+          hasLoaded.current = true;
         })
         .catch(() => setError('Failed to load patterns'))
         .finally(() => setIsFetchingPatterns(false));
     }
-  }, [expanded, patterns.length]);
+  }, [expanded]);
 
   const handleSelectAll = () => {
     setSelectedPatterns(new Set(patterns.map((p) => p.function_name)));