feat(routing): 引入多执行池智能调度

将 Worker 发现、路由画像、容量与执行传输抽象为平台无关接口，新增 Kubernetes 和静态容量适配器，并以 shadow 模式接入生产配置。

实现网络与容量评分、路由防抖、池队列、同步 Worker 租约、一次性执行令牌，以及提交状态不明时禁止重复分配的安全语义。

新增 0105 兼容迁移、管理接口、指标、OpenAPI 和回归测试。已执行全量 Go 测试、go vet、OpenAPI、迁移安全、Compose 与 Kustomize 验证。

apps/api/internal/httpapi/compat_protocol_test.go

@@ -125,10 +125,10 @@ func TestProtocolErrorsUseCompatibleShapesWithStandardPublicErrors(t *testing.T)
 			},
 		},
 		{
-			name: "volces", protocol: clients.ProtocolVolcesContents, status: http.StatusBadGateway,
+			name: "volces", protocol: clients.ProtocolVolcesContents, status: http.StatusGatewayTimeout,
 			assertBody: func(t *testing.T, body map[string]any) {
 				errorBody := requireObject(t, body["error"])
-				if errorBody["code"] != "upstream_submission_unknown" || errorBody["httpStatus"] != float64(http.StatusBadGateway) || errorBody["retryable"] != true {
+				if errorBody["code"] != "upstream_timeout" || errorBody["httpStatus"] != float64(http.StatusGatewayTimeout) || errorBody["retryable"] != true {
 					t.Fatalf("unexpected Volces error: %+v", body)
 				}
 				assertNoKeys(t, errorBody, "status", "taskId", "gateway_status")
@@ -151,7 +151,7 @@ func TestProtocolErrorsUseCompatibleShapesWithStandardPublicErrors(t *testing.T)
 			if test.name == "gemini" {
 				code = "rate_limit"
 			} else if test.name == "volces" {
-				code = "upstream_submission_unknown"
+				code = "upstream_timeout"
 			} else if test.name == "keling" {
 				code = "gateway_rate_limited"
 			}