fix: 优化 Workbench 会话列表加载

internal/workbenchruntime/service.go

@@ -1349,17 +1349,15 @@ func (s *Server) querySummaryFacts(ctx context.Context, sessions []map[string]an
 	sessionIDs := uniqueStrings(mapSessions(sessions, sessionID))
 	facts := emptyFacts()
 	if len(sessionIDs) > 0 {
-		messageSummaries, err := s.queryMessageSummaries(ctx, sessionIDs)
+		messageSummaries, messages, turns, err := s.querySessionSummaryFacts(ctx, sessionIDs)
 		if err != nil {
 			return nil, err
 		}
-		facts = mergeFacts(facts, map[string][]any{"messageSummaries": messageSummaries})
-
-		bySession, err := s.queryFacts(ctx, factQuery{SessionIDs: sessionIDs, Families: []string{"messages", "turns"}, Limit: summarySessionFactLimit(len(sessionIDs)), MessagesOrder: "updated_desc", TurnsOrder: "updated_desc"})
-		if err != nil {
-			return nil, err
-		}
-		facts = mergeFacts(facts, bySession)
+		facts = mergeFacts(facts, map[string][]any{
+			"messageSummaries": messageSummaries,
+			"messages":         messages,
+			"turns":            turns,
+		})
 	}
 	traceIDs := summaryTraceIDs(sessions, facts)
 	if len(traceIDs) > 0 {
@@ -1372,18 +1370,35 @@ func (s *Server) querySummaryFacts(ctx context.Context, sessions []map[string]an
 	return facts, nil
 }
 
-func summarySessionFactLimit(sessionCount int) int {
-	if sessionCount <= 0 {
-		return 0
+func (s *Server) querySessionSummaryFacts(ctx context.Context, sessionIDs []string) ([]any, []any, []any, error) {
+	const recentFactsPerSession = 8
+	var messageSummaries, messages, turns []any
+	var messageSummaryErr, messagesErr, turnsErr error
+	var wait sync.WaitGroup
+	wait.Add(3)
+	go func() {
+		defer wait.Done()
+		messageSummaries, messageSummaryErr = s.queryMessageSummaries(ctx, sessionIDs)
+	}()
+	go func() {
+		defer wait.Done()
+		messages, messagesErr = s.queryRecentSessionFacts(ctx, "workbench_messages", "message_json", "message_id", sessionIDs, recentFactsPerSession)
+	}()
+	go func() {
+		defer wait.Done()
+		turns, turnsErr = s.queryRecentSessionFacts(ctx, "workbench_turns", "turn_json", "turn_id", sessionIDs, recentFactsPerSession)
+	}()
+	wait.Wait()
+	if messageSummaryErr != nil {
+		return nil, nil, nil, messageSummaryErr
 	}
-	limit := sessionCount * 8
-	if limit < sessionCount {
-		return sessionCount
+	if messagesErr != nil {
+		return nil, nil, nil, messagesErr
 	}
-	if limit > 1000 {
-		return 1000
+	if turnsErr != nil {
+		return nil, nil, nil, turnsErr
 	}
-	return limit
+	return messageSummaries, messages, turns, nil
 }
 
 func summaryTraceIDs(sessions []map[string]any, facts map[string][]any) []string {
@@ -1741,6 +1756,75 @@ LEFT JOIN LATERAL (
 	return result, nil
 }
 
+func (s *Server) queryRecentSessionFacts(ctx context.Context, table string, jsonColumn string, idColumn string, sessionIDs []string, perSessionLimit int) ([]any, error) {
+	cleaned := uniqueStrings(sessionIDs)
+	if len(cleaned) == 0 || perSessionLimit <= 0 {
+		return []any{}, nil
+	}
+	if !validRecentSessionFactSource(table, jsonColumn, idColumn) {
+		return nil, wrapQueryStage("workbench_runtime.db.session_recent_facts", fmt.Errorf("unsupported recent session fact source: %s", table))
+	}
+	args := make([]any, 0, len(cleaned)+1)
+	valueRows := make([]string, 0, len(cleaned))
+	for _, sid := range cleaned {
+		args = append(args, sid)
+		valueRows = append(valueRows, fmt.Sprintf("($%d::text)", len(args)))
+	}
+	args = append(args, perSessionLimit)
+	limitPlaceholder := fmt.Sprintf("$%d", len(args))
+	sqlText := fmt.Sprintf(`SELECT recent.%s
+FROM (VALUES %s) AS requested(session_id)
+CROSS JOIN LATERAL (
+	SELECT %s, updated_at, %s
+	FROM %s
+	WHERE session_id = requested.session_id
+	ORDER BY updated_at DESC, %s DESC
+	LIMIT %s
+) AS recent
+ORDER BY recent.updated_at DESC, recent.%s DESC`, jsonColumn, strings.Join(valueRows, ", "), jsonColumn, idColumn, table, idColumn, limitPlaceholder, idColumn)
+	stage := "workbench_runtime.db." + factFamilyForTable(table) + "_recent_by_session"
+	result := []any{}
+	err := s.withOtelInternalSpan(ctx, stage, s.dbQueryAttrs(table, len(args), map[string]any{
+		"db.index.expected":        recentSessionFactExpectedIndex(table),
+		"db.query.shape":           "values_lateral_per_session_limit",
+		"db.query.session_count":   int64(len(cleaned)),
+		"db.query.per_session_max": int64(perSessionLimit),
+	}), func(spanCtx context.Context) error {
+		rows, err := s.db.QueryContext(spanCtx, sqlText, args...)
+		if err != nil {
+			return err
+		}
+		defer rows.Close()
+		for rows.Next() {
+			var raw sql.NullString
+			if err := rows.Scan(&raw); err != nil {
+				return err
+			}
+			var item any
+			if raw.Valid && strings.TrimSpace(raw.String) != "" && json.Unmarshal([]byte(raw.String), &item) == nil && item != nil {
+				result = append(result, item)
+			}
+		}
+		return rows.Err()
+	})
+	if err != nil {
+		return nil, wrapQueryStage(stage, err)
+	}
+	return result, nil
+}
+
+func validRecentSessionFactSource(table string, jsonColumn string, idColumn string) bool {
+	return table == "workbench_messages" && jsonColumn == "message_json" && idColumn == "message_id" ||
+		table == "workbench_turns" && jsonColumn == "turn_json" && idColumn == "turn_id"
+}
+
+func recentSessionFactExpectedIndex(table string) string {
+	if table == "workbench_messages" {
+		return "idx_workbench_messages_session_updated"
+	}
+	return "idx_workbench_turns_session_updated"
+}
+
 func (s *Server) queryAgentTraceEvents(ctx context.Context, query traceEventsQuery) ([]any, error) {
 	clauses := []string{}
 	args := []any{}