Enhance conversation history and runtime variable management

- Update ConversationRecorder to include source and nodeId metadata in transcripts for better context tracking.
- Introduce optional variable handling in DynamicVariableStore, allowing for unset variables to be rendered as empty without raising errors.
- Refactor WorkflowBrain to apply turn configurations and manage interaction policies dynamically, improving agent responsiveness.
- Implement tests to ensure proper handling of updated session variables and workflow metadata in various scenarios.

frontend/src/components/workflow/WorkflowEditor.tsx

@@ -78,6 +78,7 @@ import {
 import { Switch } from "@/components/ui/switch";
 import type { KnowledgeRetrievalConfig, TurnConfig } from "@/lib/api";
 import { TurnConfigEditor } from "@/components/turn-config-editor";
+import { normalizeTurnConfig } from "@/lib/turn-config";
 import { Textarea } from "@/components/ui/textarea";
 import {
   Tooltip,
@@ -195,6 +196,8 @@ function fromFlow(nodes: Node[], edges: Edge[]): WorkflowGraph {
       knowledgeMode: "automatic",
       knowledgeTopN: 5,
       knowledgeScoreThreshold: 0,
+      enableInterrupt: true,
+      turnConfig: defaultGraph().settings.turnConfig,
     },
     nodes: nodes.map((n) => ({
       id: n.id,
@@ -261,6 +264,8 @@ function Canvas({
       knowledgeTopN: settings.knowledgeRetrievalConfig.topN,
       knowledgeScoreThreshold:
         settings.knowledgeRetrievalConfig.scoreThreshold,
+      enableInterrupt: settings.allowInterrupt,
+      turnConfig: settings.turnConfig,
     };
     onChangeRef.current?.(graph);
   }, [
@@ -273,6 +278,8 @@ function Canvas({
     settings.toolIds,
     settings.knowledgeBaseId,
     settings.knowledgeRetrievalConfig,
+    settings.allowInterrupt,
+    settings.turnConfig,
   ]);
 
   const onConnect = useCallback(
@@ -1519,6 +1526,9 @@ function AgentPanelForm({
     topN: Number(draft.knowledgeTopN ?? 5),
     scoreThreshold: Number(draft.knowledgeScoreThreshold ?? 0),
   };
+  const agentTurnConfig = normalizeTurnConfig(
+    draft.turnConfig ?? workflowSettings.turnConfig,
+  );
 
   const setInheritance = (inheritGlobalConfig: boolean) => {
     if (inheritGlobalConfig) {
@@ -1550,6 +1560,9 @@ function AgentPanelForm({
       knowledgeScoreThreshold:
         draft.knowledgeScoreThreshold ??
         workflowSettings.knowledgeRetrievalConfig.scoreThreshold,
+      enableInterrupt:
+        draft.enableInterrupt ?? workflowSettings.allowInterrupt,
+      turnConfig: agentTurnConfig,
     });
   };
 
@@ -1592,10 +1605,10 @@ function AgentPanelForm({
 
       <SectionCard
         icon={<MessageSquareText size={15} />}
-        title="提示词"
+        title={inheritsGlobal ? "任务" : "提示词"}
         description={
           inheritsGlobal
-            ? "描述当前阶段任务，并与工作流全局提示词合并"
+            ? "描述当前阶段要完成的目标；角色、能力和通用规则继承工作流全局配置"
             : "描述当前独立助手的角色、能力和回答要求"
         }
       >
@@ -1603,7 +1616,11 @@ function AgentPanelForm({
           rows={8}
           value={draft.prompt ?? ""}
           onChange={(event) => set("prompt", event.target.value)}
-          placeholder="请输入提示词，描述助手的角色、能力和回答要求"
+          placeholder={
+            inheritsGlobal
+              ? "例如：确认用户身份，并收集需要查询的订单编号"
+              : "请输入提示词，描述助手的角色、能力和回答要求"
+          }
           className="field-sizing-fixed min-h-28 resize-y border-hairline-strong bg-background text-sm text-foreground placeholder:text-muted-soft"
         />
       </SectionCard>
@@ -1714,6 +1731,23 @@ function AgentPanelForm({
               onChange={(toolIds) => set("toolIds", toolIds)}
             />
           </SectionCard>
+
+          <SectionCard
+            icon={<Sparkles size={15} />}
+            title="交互策略"
+            description="配置当前 Agent 独立使用的打断和轮次检测策略"
+          >
+            <TurnConfigEditor
+              enabled={
+                draft.enableInterrupt ?? workflowSettings.allowInterrupt
+              }
+              config={agentTurnConfig}
+              onEnabledChange={(enableInterrupt) =>
+                set("enableInterrupt", enableInterrupt)
+              }
+              onConfigChange={(turnConfig) => set("turnConfig", turnConfig)}
+            />
+          </SectionCard>
         </>
       )}
     </div>