fix(auto-reply): keep typed overloaded failures on the surfaced-copy path

Shipped behavior pins overloaded FailoverErrors to immediate dedicated copy
(agent-runner-execution.test.ts 'surfaces typed overloaded failures'); only
timeout and server_error reasons join the transient retry gate.

src/auto-reply/reply/agent-runner-execution.test.ts

@@ -7867,10 +7867,6 @@ describe("runAgentTurnWithFallback", () => {
       reason: "timeout" as const,
       message: "provider request timed out without status token",
     },
-    {
-      reason: "overloaded" as const,
-      message: "provider capacity exhausted briefly",
-    },
   ])(
     "retries once for structured FailoverError $reason without leading HTTP status text",
     async ({ reason, message }) => {

src/auto-reply/reply/agent-runner-execution.ts

@@ -3084,12 +3084,11 @@ async function runAgentTurnWithFallbackInternal(
         !shouldSurfaceToControlUi
           ? classifyProviderRequestError(err)
           : undefined;
+      // Typed overloaded failures stay out of the transient retry: they surface
+      // dedicated overloaded copy immediately instead of being retried silently.
       const isTransientHttp =
         isTransientHttpError(message) ||
-        (isFailoverError(err) &&
-          (err.reason === "timeout" ||
-            err.reason === "server_error" ||
-            err.reason === "overloaded"));
+        (isFailoverError(err) && (err.reason === "timeout" || err.reason === "server_error"));
 
       // Drain/restart aborts stay silent and defer to post-restart
       // main-session recovery, which resumes the interrupted turn (or emits its