fix(gateway): handle async EPIPE on stdout/stderr during shutdown (#13414)

* fix(gateway): handle async EPIPE on stdout/stderr during shutdown

The console capture forward() wrapper catches synchronous EPIPE errors,
but when the receiving pipe closes during shutdown Node emits the error
asynchronously on the stream. Without a listener this becomes an
uncaught exception that crashes the gateway, causing macOS launchd to
permanently unload the service.

Add error listeners on process.stdout and process.stderr inside
enableConsoleCapture() that silently swallow EPIPE/EIO (matching the
existing isEpipeError helper) and re-throw anything else.

Closes #13367

* guard stream error listeners against repeated enableConsoleCapture() calls

Use a separate streamErrorHandlersInstalled flag in loggingState so that
test resets of consolePatched don't cause listener accumulation on
process.stdout/stderr.

src/logging/console-capture.test.ts

@@ -121,6 +121,30 @@ describe("enableConsoleCapture", () => {
     console.log(payload);
     expect(log).toHaveBeenCalledWith(payload);
   });
+
+  it("swallows async EPIPE on stdout", () => {
+    setLoggerOverride({ level: "info", file: tempLogPath() });
+    enableConsoleCapture();
+    const epipe = new Error("write EPIPE") as NodeJS.ErrnoException;
+    epipe.code = "EPIPE";
+    expect(() => process.stdout.emit("error", epipe)).not.toThrow();
+  });
+
+  it("swallows async EPIPE on stderr", () => {
+    setLoggerOverride({ level: "info", file: tempLogPath() });
+    enableConsoleCapture();
+    const epipe = new Error("write EPIPE") as NodeJS.ErrnoException;
+    epipe.code = "EPIPE";
+    expect(() => process.stderr.emit("error", epipe)).not.toThrow();
+  });
+
+  it("rethrows non-EPIPE errors on stdout", () => {
+    setLoggerOverride({ level: "info", file: tempLogPath() });
+    enableConsoleCapture();
+    const other = new Error("EACCES") as NodeJS.ErrnoException;
+    other.code = "EACCES";
+    expect(() => process.stdout.emit("error", other)).toThrow("EACCES");
+  });
 });
 
 function tempLogPath() {