fix(test): daemon 503 test binds an OS-assigned port, not old-port+1

windows-free-tests flaked on this PR: the tunnel-less restart bound
daemon.loopbackPort + 1 — a fixed neighbor of the OS-assigned ephemeral
port — and died with 'Is port 55738 in use?' whenever another shard or a
TIME_WAIT socket held it; the file-level retry re-rolled the same dice.
Every other startDaemon in the file already uses loopbackPort: 0 and the
assertion reads d2.loopbackPort, so nothing needs a predictable number.
21/21 pass locally.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

ios-qa/daemon/test/daemon-integration.test.ts

@@ -466,7 +466,12 @@ describe('daemon — loopback listener', () => {
     await daemon.close();
     pidPath = join(workDir, 'daemon-2.pid');
     const d2 = await startDaemon({
-      loopbackPort: daemon.loopbackPort + 1,
+      // OS-assigned like every other start in this file — the old
+      // `daemon.loopbackPort + 1` bound a fixed neighbor port and flaked
+      // whenever another shard/TIME_WAIT socket held it (windows-free-tests:
+      // "Is port 55738 in use?"). The fetch below reads d2.loopbackPort, so
+      // nothing needs a predictable number.
+      loopbackPort: 0,
       tailnetEnabled: false,
       pidfilePath: pidPath,
       tunnelProvider: async () => null,