feat(channel): add quoted message context injection for Discord and Feishu

Prepend replied-to message text and attachments into the user query so
the LLM can see what is being replied to, matching the existing Telegram
behavior. Also set is_reply_to_bot metadata for Feishu reply-to-bot
detection in group chats.

internal/channel/adapters/feishu/webhook_handler.go

@@ -110,6 +110,7 @@ func (h *WebhookHandler) Handle(c echo.Context) error {
 			return nil
 		}
 		h.adapter.enrichSenderProfile(reqCtx, cfg, event, &msg)
+		h.adapter.enrichQuotedMessage(reqCtx, cfg, &msg, botOpenID)
 		msg.BotID = cfg.BotID
 		return h.manager.HandleInbound(reqCtx, cfg, msg)
 	})