Fix fallback log message never emitted due to mutated state

Capture the requested serverExposureMode before calling
applyDesktopServerExposureMode, which mutates desktopSettings.
The fallback diagnostic check now compares against the original
requested mode instead of the already-overwritten value.

Author: cursoragent

apps/desktop/src/main.ts

@@ -1667,18 +1667,16 @@ async function bootstrap(): Promise<void> {
       `bootstrap restoring persisted server exposure mode mode=${desktopSettings.serverExposureMode}`,
     );
   }
-  const serverExposureState = await applyDesktopServerExposureMode(
-    desktopSettings.serverExposureMode,
-    {
-      persist: desktopSettings.serverExposureMode !== DEFAULT_DESKTOP_SETTINGS.serverExposureMode,
-    },
-  );
+  const requestedExposureMode = desktopSettings.serverExposureMode;
+  const serverExposureState = await applyDesktopServerExposureMode(requestedExposureMode, {
+    persist: requestedExposureMode !== DEFAULT_DESKTOP_SETTINGS.serverExposureMode,
+  });
   writeDesktopLogHeader(`bootstrap resolved backend endpoint baseUrl=${backendHttpUrl}`);
   if (serverExposureState.endpointUrl) {
     writeDesktopLogHeader(
       `bootstrap enabled network access endpointUrl=${serverExposureState.endpointUrl}`,
     );
-  } else if (desktopSettings.serverExposureMode === "network-accessible") {
+  } else if (requestedExposureMode === "network-accessible") {
     writeDesktopLogHeader(
       "bootstrap fell back to local-only because no advertised network host was available",
     );