refactor(dispatcher): T1.1 退役 graph.go —— 编排引擎收成单一 compose

compose 已默认数天、HITL/多智能体/评测全在其上真实跑过，soak 充分。删掉自研拓扑
解释器这第二套引擎，消灭"双实现 drift"税：

- 删 runGraph（graph.go 的自研解释器）+ composeEnabled/EINO_COMPOSE 逃生舱开关
  + runConversation（仅 runGraph 用的死代码）。
- executeGraph 直接走 runComposeGraph；compose 编译失败兜底改单轮对话（不再回退
  graph.go）；清掉仅 runGraph 用的 import（otel attribute/trace/otelx）。
- 保留 board / 各节点执行器(retriever/tool/agent/branch/approval/map/render/aggregate)
  / 工具函数 —— 它们是 compose 各节点 lambda 复用的，非 graph.go 专属。
- 测试：8 处 runGraph→runComposeGraph；等价测试(对照两引擎)转为 compose 正确性测试；
  runConversation 的开关测试转为「无 ChatModel 降级 runAgent」。

go test ./... 全绿 + vet 干净；冒烟 简单 agent/分支图 跑通。此后每个编排改动不再两边
对齐，成本减半。DEPTH_ROADMAP T1.1 ✅。

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

sundynix-dispatcher/internal/eino/compose_compiler_test.go

@@ -28,21 +28,15 @@ func echoLLM() *fakeLLM {
 	}
 }
 
-func runBoth(t *testing.T, graph string) (interp, comp string) {
+// runCompose 跑一个图并返回成稿（自研 graph.go 已退役，编排引擎统一为 compose）。
+func runCompose(t *testing.T, graph string) string {
 	t.Helper()
-	task := &contract.Task{ID: "t_eq", Graph: []byte(graph)}
-
-	o1 := &Orchestrator{pool: echoLLM(), breaker: harness.NewCircuitBreaker(), sink: &fakeSink{}}
-	a1, _, err := o1.runGraph(context.Background(), task, &execTracer{})
-	if err != nil {
-		t.Fatalf("runGraph: %v", err)
-	}
-	o2 := &Orchestrator{pool: echoLLM(), breaker: harness.NewCircuitBreaker(), sink: &fakeSink{}}
-	a2, _, err := o2.runComposeGraph(context.Background(), task, &execTracer{})
+	o := &Orchestrator{pool: echoLLM(), breaker: harness.NewCircuitBreaker(), sink: &fakeSink{}}
+	ans, _, err := o.runComposeGraph(context.Background(), &contract.Task{ID: "t_eq", Graph: []byte(graph)}, &execTracer{})
 	if err != nil {
 		t.Fatalf("runComposeGraph: %v", err)
 	}
-	return a1, a2
+	return ans
 }
 
 // rejectWaiter 是恒拒绝的 HITL 审批替身（fail-safe 路径回归用）。
@@ -257,8 +251,8 @@ func TestComposeReturnsRefs(t *testing.T) {
 	}
 }
 
-// TestComposeEquivalentLinear 多节点线性图：input→memory→agent→output，两路径成稿应逐字一致。
-func TestComposeEquivalentLinear(t *testing.T) {
+// TestComposeLinear 多节点线性图：input→memory→agent→output，compose 应跑通并产出成稿。
+func TestComposeLinear(t *testing.T) {
 	graph := `{"version":"1","nodes":[
 		{"id":"in","kind":"input","config":{"text":"什么是图编排"}},
 		{"id":"m","kind":"memory","config":{}},
@@ -267,14 +261,14 @@ func TestComposeEquivalentLinear(t *testing.T) {
 	],"edges":[
 		{"source":"in","target":"m"},{"source":"m","target":"a"},{"source":"a","target":"out"}
 	]}`
-	interp, comp := runBoth(t, graph)
-	if interp == "" || interp != comp {
-		t.Fatalf("线性图不等价: interp=%q compose=%q", interp, comp)
+	if ans := runCompose(t, graph); !strings.Contains(ans, "ANS:") {
+		t.Fatalf("线性图 compose 应产出成稿，got %q", ans)
 	}
 }
 
-// TestComposeEquivalentBranch 分支图：input→branch→(真)A/(假)B，条件恒真应都走 A，两路径一致。
-func TestComposeEquivalentBranch(t *testing.T) {
+// TestComposeBranch 分支图：input→branch→(真)A/(假)B，条件恒真走 A，compose 应跑通产出。
+// 分支真假边的精确选路另由 TestRunGraph_BranchRouting（compose）钉死。
+func TestComposeBranch(t *testing.T) {
 	graph := `{"version":"1","nodes":[
 		{"id":"in","kind":"input","config":{"text":"hi"}},
 		{"id":"br","kind":"branch","config":{"condition":""}},
@@ -285,8 +279,7 @@ func TestComposeEquivalentBranch(t *testing.T) {
 		{"source":"br","target":"a","sourceHandle":"true"},
 		{"source":"br","target":"b","sourceHandle":"false"}
 	]}`
-	interp, comp := runBoth(t, graph)
-	if interp == "" || interp != comp {
-		t.Fatalf("分支图不等价: interp=%q compose=%q", interp, comp)
+	if ans := runCompose(t, graph); !strings.Contains(ans, "ANS:") {
+		t.Fatalf("分支图 compose 应产出成稿，got %q", ans)
 	}
 }