Fix: skip Tailscale endpoint resolution in local-only mode

In local-only mode the backend binds to 127.0.0.1, so Tailscale CGNAT
addresses (100.64.x.y) are unreachable. However, resolveTailscaleAdvertisedEndpoints
was called unconditionally, producing endpoints marked as 'available' that
would rank higher than the working loopback endpoint during selection.

Return only core endpoints when exposure mode is 'local-only'.

Author: cursoragent

apps/desktop/src/main.ts

@@ -326,6 +326,9 @@ async function getDesktopAdvertisedEndpoints() {
     exposure,
     customHttpsEndpointUrls: resolveCustomHttpsEndpointUrls(),
   });
+  if (exposure.mode === "local-only") {
+    return coreEndpoints;
+  }
   const tailscaleEndpoints = await resolveTailscaleAdvertisedEndpoints({
     port: backendPort,
     networkInterfaces: OS.networkInterfaces(),