feat: 全链路追踪系统 — ai-core追踪事件 + ethend管道视图

ai-core:
- 新增 TraceEvent 内存环形缓冲区(200条)
- GET /api/v1/trace/events 端点（支持session_id过滤）
- 预置 trace.go 追踪事件定义

ethend:
- trace/recent 聚合 platform-bridge消息日志 + ai-core追踪事件
- 消息按管线分组: msg_received→llm_call→tool_call→msg_sent
- 前端管线卡片视图: 每条消息显示完整处理步骤

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

backend/ai-core/cmd/main.go

@@ -426,6 +426,9 @@ func main() {
 	// 健康检查与对话API的HTTP mux
 	mux := http.NewServeMux()
 
+	// 注册全链路追踪事件端点
+	registerTraceEndpoint(mux)
+
 	// 初始化子会话管理器
 	subManager := subsession.NewManager(chatAdapter)
 

backend/ai-core/cmd/trace.go

@@ -0,0 +1,87 @@
+package main
+
+import (
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"strconv"
+	"sync"
+	"time"
+)
+
+// TraceEvent represents a single step in the message processing pipeline.
+type TraceEvent struct {
+	ID        string    `json:"id"`
+	Timestamp time.Time `json:"timestamp"`
+	SessionID string    `json:"session_id,omitempty"`
+	UserID    string    `json:"user_id,omitempty"`
+	Hop       string    `json:"hop"`       // message_received, intent, subsession, llm_call, tool_call, vision, synthesis, review, response, think
+	Label     string    `json:"label"`
+	Status    string    `json:"status"`    // success, error, running
+	Detail    string    `json:"detail,omitempty"`
+	DurationMs int64   `json:"duration_ms,omitempty"`
+	Data      map[string]interface{} `json:"data,omitempty"`
+}
+
+var (
+	traceMu     sync.Mutex
+	traceEvents []TraceEvent
+	traceMax    = 200
+)
+
+// AddTraceEvent appends a trace event to the in-memory ring buffer.
+func AddTraceEvent(hop, sessionID, userID, label, status, detail string, durationMs int64, data map[string]interface{}) {
+	traceMu.Lock()
+	defer traceMu.Unlock()
+	ev := TraceEvent{
+		ID:         fmt.Sprintf("%s-%d", hop, time.Now().UnixNano()),
+		Timestamp:  time.Now(),
+		SessionID:  sessionID,
+		UserID:     userID,
+		Hop:        hop,
+		Label:      label,
+		Status:     status,
+		Detail:     detail,
+		DurationMs: durationMs,
+		Data:       data,
+	}
+	traceEvents = append(traceEvents, ev)
+	if len(traceEvents) > traceMax {
+		traceEvents = traceEvents[len(traceEvents)-traceMax:]
+	}
+}
+
+// GetTraceEvents returns recent trace events, optionally filtered by session.
+func GetTraceEvents(sessionID string, limit int) []TraceEvent {
+	traceMu.Lock()
+	defer traceMu.Unlock()
+	if limit <= 0 || limit > len(traceEvents) {
+		limit = len(traceEvents)
+	}
+	var result []TraceEvent
+	// Return newest first.
+	for i := len(traceEvents) - 1; i >= 0 && len(result) < limit; i-- {
+		ev := traceEvents[i]
+		if sessionID == "" || ev.SessionID == sessionID {
+			result = append(result, ev)
+		}
+	}
+	return result
+}
+
+// registerTraceEndpoint adds the trace events API.
+func registerTraceEndpoint(mux *http.ServeMux) {
+	mux.HandleFunc("/api/v1/trace/events", func(w http.ResponseWriter, r *http.Request) {
+		sessionID := r.URL.Query().Get("session_id")
+		limit := 100
+		if l, err := strconv.Atoi(r.URL.Query().Get("limit")); err == nil && l > 0 && l <= 500 {
+			limit = l
+		}
+		events := GetTraceEvents(sessionID, limit)
+		w.Header().Set("Content-Type", "application/json")
+		json.NewEncoder(w).Encode(map[string]interface{}{
+			"events": events,
+			"total":  len(events),
+		})
+	})
+}

ethend/public/index.html

@@ -6284,15 +6284,51 @@ async function refreshTrace() {
     }
   }
 
-  // 如果是首次加载（content 只有 loading 提示），全量渲染
+  // Try pipeline view first (new format)
+  var pipelines = data.pipelines || [];
+  if (pipelines.length > 0) {
+    var html = '<div class="trace-timeline">';
+    for (var pi = 0; pi < pipelines.length; pi++) {
+      var pl = pipelines[pi];
+      var steps = pl.steps || [];
+      var hasMsg = steps.some(function(s){ return s.hop === 'msg_received'; });
+      html += '<div class="trace-pipeline" style="margin:12px 0;border:1px solid var(--border);border-radius:8px;overflow:hidden">';
+      // Pipeline header
+      html += '<div style="padding:8px 12px;background:var(--bg2);display:flex;justify-content:space-between;align-items:center">';
+      html += '<span style="font-weight:600;font-size:13px">📨 ' + escHtml(pl.sender || '?') + (pl.platform ? ' · ' + escHtml(pl.platform) : '') + '</span>';
+      html += '<span style="font-size:11px;color:var(--text2)">' + (pl.timestamp || '').substring(11,19) + '</span>';
+      html += '</div>';
+      // Pipeline steps
+      html += '<div style="padding:4px 0">';
+      for (var si = 0; si < steps.length; si++) {
+        var s = steps[si];
+        var hopIcon = {msg_received:'📥',msg_sent:'📤',llm_call:'🧠',tool_call:'🔧',session:'👤'}[s.hop] || '●';
+        var hopColor = s.status === 'error' ? 'var(--red)' : (s.hop === 'msg_received' ? 'var(--blue)' : s.hop === 'msg_sent' ? 'var(--green)' : 'var(--text2)');
+        html += '<div style="display:flex;align-items:flex-start;padding:4px 12px;gap:8px;font-size:12px">';
+        html += '<span style="color:' + hopColor + ';flex-shrink:0;width:20px;text-align:center">' + hopIcon + '</span>';
+        html += '<span style="flex:1"><b>' + escHtml(s.label) + '</b>';
+        if (s.detail) html += '<br><span style="color:var(--text2);font-size:11px">' + escHtml(s.detail) + '</span>';
+        if (s.durationMs > 0) html += ' <span style="color:var(--text3);font-size:10px">(' + (s.durationMs >= 1000 ? (s.durationMs/1000).toFixed(1)+'s' : s.durationMs+'ms') + ')</span>';
+        html += '</span></div>';
+      }
+      html += '</div></div>';
+    }
+    html += '</div>';
+    contentEl.innerHTML = html;
+    // Also update stats
+    updateTraceStatsEl(statsEl, traces, stats, data.session);
+    return;
+  }
+
+  // Fallback: flat timeline
   var timeline = contentEl.querySelector('.trace-timeline');
   if (!timeline) {
-    if (traces.length === 0) {
+    if (traces.length === 0 && pipelines.length === 0) {
       contentEl.innerHTML = '<div class="trace-empty"><div class="icon">📭</div>暂无链路追踪数据<br><span style="font-size:11px;color:var(--text3)">请确保服务正在运行且有消息活动</span></div>';
       statsEl.innerHTML = '';
       return;
     }
-    // 全量渲染
+    // 全量渲染 (old format)
     var html = '<div class="trace-timeline">';
     for (var i = 0; i < traces.length; i++) {
       html += traceHopHtml(traces[i], i > 0 ? traces[i-1] : null);

ethend/src/index.js

@@ -1277,16 +1277,16 @@ function parseLogTimestamp(line) {
 app.get('/api/trace/recent', async (req, res) => {
   const limit = Math.min(parseInt(req.query.limit) || 50, 200);
   try {
-    const [llmResult, toolResult, sessionsResult, bridgeLogsResult, aiCoreLogsResult] = await Promise.all([
+    const [llmResult, toolResult, sessionsResult, bridgeLogsResult, traceEventsResult] = await Promise.all([
       proxyToAICore(`/api/v1/llm-calls?limit=${limit}`).catch(() => ({ status: 502, body: [] })),
       proxyToAICore(`/api/v1/tools/calls?limit=${limit}`).catch(() => ({ status: 502, body: { calls: [] } })),
       proxyToGateway('/api/v1/admin/sessions/active').catch(() => ({ status: 502, body: { users: {} } })),
       // 拉 platform-bridge 最近的消息日志
-      Promise.all((['obv11', 'qq']).map(platform =>
+      Promise.all((['obv11']).map(platform =>
-        proxyToPlatformBridge(`/api/v1/logs/${platform}?limit=50`).catch(() => ({ status: 502, body: { entries: [] } }))
+        proxyToPlatformBridge(`/api/v1/logs/${platform}?limit=50`).catch(() => ({ status: 502, body: { logs: [] } }))
       )),
-      // 拉 ai-core 最近的日志（解析处理事件）
+      // 拉 ai-core 追踪事件
-      proxyToAICore('/api/v1/llm-calls/stream?limit=0').catch(() => ({ status: 502, body: [] })),
+      proxyToAICore(`/api/v1/trace/events?limit=${limit}`).catch(() => ({ status: 502, body: { events: [] } })),
     ]);
 
     const traces = [];
@@ -1349,6 +1349,23 @@ app.get('/api/trace/recent', async (req, res) => {
       });
     }
 
+    // === ai-core 追踪事件 (intent, subsession, synthesis, etc.) ===
+    const traceEvents = traceEventsResult.body?.events || [];
+    for (const ev of traceEvents) {
+      const ts = ev.timestamp ? new Date(ev.timestamp).getTime() : Date.now();
+      traces.push({
+        id: ev.id || `trace-${ts}`,
+        timestamp: new Date(ts).toISOString(), ts,
+        service: 'ai-core',
+        hop: ev.hop || 'trace',
+        label: ev.label || '',
+        status: ev.status || 'success',
+        durationMs: ev.duration_ms || 0,
+        detail: ev.detail || '',
+        data: ev.data || {},
+      });
+    }
+
     // === 活跃会话 ===
     const users = sessionsResult.body?.users || {};
     for (const [userID, sessions] of Object.entries(users)) {