fix: restrict requireMentionInThread to topic-thread groups only

Plain quote-replies in normal groups also set threadReply=true (via
root_id), which would incorrectly bypass the mention gate. Now only
apply the thread override when the group is in topic-thread mode
(group_topic or group_topic_sender).

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

extensions/feishu/src/bot.ts

@@ -414,7 +414,10 @@ export async function handleFeishuMessage(params: {
 
     ({ requireMention } = resolveFeishuReplyPolicy({
       isDirectMessage: false,
-      isThreadReply: groupSession?.threadReply,
+      isThreadReply:
+        groupSession?.threadReply &&
+        (groupSession?.groupSessionScope === "group_topic" ||
+          groupSession?.groupSessionScope === "group_topic_sender"),
       globalConfig: feishuCfg,
       groupConfig,
     }));