Fix: AI topics now appear FIRST in hot topics (insert(0) instead of append)

Changed append to insert(0) so AI topics like Công nghệ AI, World Cup 2026 appear at the top

app_v2_entry.py

@@ -484,7 +484,7 @@ def _get_hot_topics():
         if len(topics)>=20:break
     for kw in['World Cup 2026','Kinh tế Việt Nam','Bóng đá châu Âu','Công nghệ AI','Giá vàng','Thời tiết']:
         if len(topics)>=24:break
-        if not any(kw.lower() in s for s in seen):topics.append({'label':'#'+re.sub(r'\s+','',kw.title()),'topic':kw,'count':0})
+        if not any(kw.lower() in s for s in seen):topics.insert(0,{'label':'#'+re.sub(r'\s+','',kw.title()),'topic':kw,'count':0})
     _hot_cache.update({'t':now,'d':topics[:24]});return topics[:24]
 
 @app.get('/api/hot_topics')