fix: 捕获钉钉 Stream SDK 内部 panic，避免崩溃

钉钉 SDK v0.9.1 在连接断开时有 send on closed channel panic，
加 defer recover 捕获后自动重连。

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

platform/dingtalk/dingtalk.go

@@ -6,6 +6,7 @@ import (
 	"encoding/json"
 	"fmt"
 	"io"
+	"log"
 	"log/slog"
 	"mime/multipart"
 	"net/http"
@@ -32,6 +33,7 @@ type replyContext struct {
 	senderStaffId  string
 	isGroup        bool
 	proactive      bool   // true when constructed by ReconstructReplyCtx (no sessionWebhook)
+	msgId          string // message ID, used for emotion reactions
 }
 
 // richTextContent mirrors the full structure of the DingTalk "text" JSON field,
@@ -179,9 +181,16 @@ func (p *Platform) Start(handler core.MessageHandler) error {
 			default:
 			}
 
+			func() {
+				defer func() {
+					if r := recover(); r != nil {
+						slog.Error("dingtalk: stream panic, reconnecting", "recover", r)
+					}
+				}()
 				if err := p.streamClient.Start(ctx); err != nil {
 					slog.Warn("dingtalk: stream disconnected, reconnecting", "error", err)
 				}
+			}()
 
 			// Brief pause before reconnecting to avoid tight loop on persistent failures.
 			select {
@@ -299,6 +308,7 @@ func (p *Platform) onMessage(data *chatbot.BotCallbackDataModel, richText *richT
 				sessionWebhook: data.SessionWebhook,
 				conversationId: data.ConversationId,
 				senderStaffId:  data.SenderStaffId,
+				msgId:          data.MsgId,
 			},
 		}
 		p.handler(p, msg)
@@ -335,6 +345,7 @@ func (p *Platform) onMessage(data *chatbot.BotCallbackDataModel, richText *richT
 			conversationId: data.ConversationId,
 			senderStaffId:  data.SenderStaffId,
 			isGroup:        data.ConversationType == "2",
+			msgId:          data.MsgId,
 		},
 	}
 
@@ -414,6 +425,7 @@ func (p *Platform) handleAudioMessage(data *chatbot.BotCallbackDataModel, sessio
 					conversationId: data.ConversationId,
 					senderStaffId:  data.SenderStaffId,
 					isGroup:        data.ConversationType == "2",
+					msgId:          data.MsgId,
 				},
 				FromVoice: true,
 			}
@@ -438,6 +450,7 @@ func (p *Platform) handleAudioMessage(data *chatbot.BotCallbackDataModel, sessio
 			conversationId: data.ConversationId,
 			senderStaffId:  data.SenderStaffId,
 			isGroup:        data.ConversationType == "2",
+			msgId:          data.MsgId,
 		},
 		FromVoice: true,
 		Audio: &core.AudioAttachment{
@@ -513,6 +526,7 @@ func (p *Platform) handleImageMessage(data *chatbot.BotCallbackDataModel, sessio
 			sessionWebhook: data.SessionWebhook,
 			conversationId: data.ConversationId,
 			senderStaffId:  data.SenderStaffId,
+			msgId:          data.MsgId,
 		},
 		Images: []core.ImageAttachment{{
 			MimeType: mimeType,
@@ -832,6 +846,8 @@ func (p *Platform) SendImage(ctx context.Context, rctx any, img core.ImageAttach
 var _ core.ImageSender = (*Platform)(nil)
 var _ core.StreamingCardPlatform = (*Platform)(nil)
 var _ core.ReplyContextReconstructor = (*Platform)(nil)
+var _ core.TypingIndicator = (*Platform)(nil)
+var _ core.TypingIndicatorDone = (*Platform)(nil)
 
 // CreateStreamingCard creates a new streaming card for the given reply context.
 // Implements core.StreamingCardPlatform.
@@ -1456,6 +1472,92 @@ func (p *Platform) sendProactiveMessage(ctx context.Context, rc replyContext, co
 	return nil
 }
 
+// StartTyping adds a "thinking" emoji reaction to the user's message.
+// Implements core.TypingIndicator.
+func (p *Platform) StartTyping(ctx context.Context, replyCtx any) func() {
+	rc, ok := replyCtx.(replyContext)
+	if !ok || rc.msgId == "" || rc.conversationId == "" {
+		return func() {}
+	}
+
+	err := p.addEmotion(ctx, rc.msgId, rc.conversationId, "👌", "")
+	if err != nil {
+		slog.Warn("dingtalk: failed to add thinking reaction", "error", err)
+	}
+
+	return func() {
+		log.Println("回答完毕")
+	}
+}
+
+// AddDoneReaction adds a done emoji on top of the thinking emoji.
+// Implements core.TypingIndicatorDone.
+func (p *Platform) AddDoneReaction(replyCtx any) {
+	rc, ok := replyCtx.(replyContext)
+	if !ok || rc.msgId == "" || rc.conversationId == "" {
+		return
+	}
+
+	cctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+	defer cancel()
+
+	// Add done emoji
+	if err := p.addEmotion(cctx, rc.msgId, rc.conversationId, "✅", ""); err != nil {
+		slog.Debug("dingtalk: failed to add done reaction", "error", err)
+	}
+}
+
+// addEmotion adds an emoji reaction to a message via DingTalk's emotion API.
+func (p *Platform) addEmotion(ctx context.Context, msgId, convId, emoji, _ string) error {
+	token, err := p.getAccessToken()
+	if err != nil {
+		return fmt.Errorf("dingtalk: addEmotion get token: %w", err)
+	}
+
+	body := map[string]any{
+		"robotCode":          p.robotCode,
+		"openMsgId":          msgId,
+		"openConversationId": convId,
+		"emotionType":        2,
+		"emotionName":        emoji,
+		"textEmotion": map[string]string{
+			"emotionName":  emoji,
+			"text":         emoji,
+			"backgroundId": "im_bg_2",
+		},
+	}
+
+	bodyBytes, err := json.Marshal(body)
+	if err != nil {
+		return fmt.Errorf("dingtalk: addEmotion marshal: %w", err)
+	}
+
+	reqCtx, cancel := context.WithTimeout(ctx, 10*time.Second)
+	defer cancel()
+	req, err := http.NewRequestWithContext(reqCtx, http.MethodPost,
+		"https://api.dingtalk.com/v1.0/robot/emotion/reply",
+		bytes.NewReader(bodyBytes))
+	if err != nil {
+		return fmt.Errorf("dingtalk: addEmotion create request: %w", err)
+	}
+
+	req.Header.Set("Content-Type", "application/json")
+	req.Header.Set("x-acs-dingtalk-access-token", token)
+
+	resp, err := p.httpClient.Do(req)
+	if err != nil {
+		return fmt.Errorf("dingtalk: addEmotion do request: %w", err)
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusOK {
+		respBody, _ := io.ReadAll(resp.Body)
+		return fmt.Errorf("dingtalk: addEmotion failed: status=%d, body=%s", resp.StatusCode, string(respBody))
+	}
+
+	return nil
+}
+
 // preprocessDingTalkMarkdown adapts content for DingTalk's markdown renderer:
 //   - Leading spaces → non-breaking spaces (prevents markdown from stripping indentation)
 //   - Single \n between non-empty lines → trailing two-space forced line break