feat(managed): default the steward and managed Turns to one execution profile

apps/presentation/dashboard/src/data/chat.ts

@@ -100,6 +100,10 @@ export const managerChannelBindingSchema = z.object({
   schema_version: z.string(),
   executor_endpoint: z.string(),
   executor_endpoint_source: z.string(),
+  // Why the shipped default resolved the way it did. Present so a conditional
+  // default reads as a decision with a reason instead of an incidental
+  // environment value; empty when the operator selected the endpoint explicitly.
+  executor_endpoint_default_reason: z.string().optional(),
   executor_kind: z.string(),
   model: z.string(),
   model_source: z.string(),

apps/presentation/dashboard/src/features/personal-workspace/channel-header.tsx

@@ -97,6 +97,30 @@
         : t("header.managerExecutorKindRegistered")
     : null;
   const managerExecutionUnavailable = managerChannelBinding?.available === false;
+  // Name the reason instead of one hardcoded host: the channel can hold the
+  // managed host through its segment transport now, so "this channel needs
+  // codex" would be both wrong and unactionable. An unknown reason stays
+  // unclaimed rather than being rendered as a reason this build invented.
+  const managerExecutionUnavailableReason = managerChannelBinding?.available === false
+    ? managerChannelBinding.unavailable_reason
+    : null;
+  const managerExecutionUnavailableKey = managerExecutionUnavailableReason === "operator_credential_unconfigured"
+    ? "header.managerExecutionUnavailableCredential"
+    : managerExecutionUnavailableReason === "dsh_runtime_unavailable"
+      ? "header.managerExecutionUnavailableRuntime"
+      : managerExecutionUnavailableReason === "invalid_reasoning_effort"
+        ? "header.managerExecutionUnavailableEffort"
+        : "header.managerExecutionUnavailable";
+  // The shipped default is conditional, so the chip says which branch it took
+  // and why; without this a steward on codex looks identical whether the
+  // operator chose it or the machine simply had no credential.
+  const managerExecutionDefaultReason = managerChannelBinding
+    && managerChannelBinding.executor_endpoint_source === "product_default"
+    && (managerChannelBinding.executor_endpoint_default_reason ?? "") !== ""
+    ? managerChannelBinding.executor_endpoint_default_reason === "operator_credential_absent"
+      ? "header.managerEndpointWithoutCredential"
+      : "header.managerEndpointFromCredential"
+    : null;
 
   return (
     <header className="personal-channel-header">
@@ -123,7 +147,15 @@
             </span>
             {managerExecutionUnavailable ? (
               <span className="personal-execution-note">
-                {t("header.managerExecutionUnavailable", { executor: managerChannelBinding.executor_endpoint })}
+                {t(managerExecutionUnavailableKey, {
+                  executor: managerChannelBinding.executor_endpoint,
+                  credential: managerChannelBinding.credential_env_var,
+                })}
+              </span>
+            ) : null}
+            {managerExecutionDefaultReason ? (
+              <span className="personal-execution-rule-note">
+                {t(managerExecutionDefaultReason, { executor: managerChannelBinding.executor_endpoint })}
               </span>
             ) : null}
           </p>

apps/presentation/dashboard/src/features/personal-workspace/i18n.tsx

@@ -408,7 +408,12 @@ const en = {
   "header.managerExecutorKindIndividual": "individual CLI login",
   "header.managerExecutorKindManaged": "operator credential",
   "header.managerExecutorKindRegistered": "registered endpoint",
-  "header.managerExecutionUnavailable": "Selected {executor} has no Chat transport yet; this channel needs codex, or run the managed host through loopx turn.",
+  "header.managerExecutionUnavailable": "Selected {executor} cannot start here; this channel does not fall back to an individual CLI login.",
+  "header.managerExecutionUnavailableCredential": "Selected {executor} needs the operator credential {credential} before this channel can start it.",
+  "header.managerExecutionUnavailableRuntime": "Selected {executor} cannot start here because its runtime is not installed on this machine.",
+  "header.managerExecutionUnavailableEffort": "Selected {executor} rejected the configured reasoning effort; set a supported effort and reload.",
+  "header.managerEndpointFromCredential": "Selected {executor} because the operator credential is configured.",
+  "header.managerEndpointWithoutCredential": "Selected {executor} because no operator credential is configured on this machine.",
   "header.managerOverview": "Overview",
   "header.managerView": "Manager view",
   "header.openGoalNavigation": "Open Goal navigation",
@@ -1412,7 +1417,12 @@ const zhCN: Record<WorkspaceMessageKey, string> = {
   "header.managerExecutorKindIndividual": "个人 CLI 登录",
   "header.managerExecutorKindManaged": "operator 凭据",
   "header.managerExecutorKindRegistered": "注册端点",
-  "header.managerExecutionUnavailable": "所选执行器 {executor} 尚无 Chat 通道；管家通道需要 codex，托管宿主请走 loopx turn。",
+  "header.managerExecutionUnavailable": "所选执行器 {executor} 无法在本机启动；该通道不会回落到个人 CLI 登录。",
+  "header.managerExecutionUnavailableCredential": "所选执行器 {executor} 需要 operator 凭据 {credential}，配置后该通道才能启动它。",
+  "header.managerExecutionUnavailableRuntime": "所选执行器 {executor} 无法在本机启动：本机未安装其 runtime。",
+  "header.managerExecutionUnavailableEffort": "所选执行器 {executor} 拒绝了当前配置的推理档位；请改为受支持的档位后刷新。",
+  "header.managerEndpointFromCredential": "因为已配置 operator 凭据，当前选择 {executor}。",
+  "header.managerEndpointWithoutCredential": "因为本机未配置 operator 凭据，当前选择 {executor}。",
   "header.managerOverview": "总览",
   "header.managerView": "管家视图",
   "header.openGoalNavigation": "打开 Goal 导航",