[BUG] Dispatch: messages marked Read but no response delivered (Windows, post-reinstall)

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

After a clean reinstall of Claude Desktop (Windows) and the Claude mobile app (Android), re-pairing Dispatch succeeds, but every message sent from the mobile app is marked ✓ Read on both the phone and the desktop Dispatch pane, then hangs indefinitely. No response ever renders on either client. This matches the symptom pattern of #40178, #40179, #40430 — and critically persisted through a full uninstall + reinstall on both ends, which rules out stale local state.

What Should Happen?

Response text (and any file writes) appear in the Dispatch thread on both desktop and mobile, and written files show up in the Outputs panel.
Actual:

• Messages marked ✓ Read on both ends
• Thinking indicator spins indefinitely
• No response text on either client
• Outputs panel remains empty
• No error surfaced in the UI

Error Messages/Logs

Steps to Reproduce

1. Uninstall Claude Desktop (Windows) and Claude mobile app (Android). Reinstall both from scratch.
2. Sign in to the same Anthropic account on both.
3. On Desktop: Cowork → Dispatch → Get started → Finish setup. QR code displayed.
4. On Android: Claude app → Dispatch tab → scan QR. Pairing confirmed instantly.
5. From the phone, send a trivial message: e.g. ok do you function? then write a test.txt file containing the word test.
6. Observe on desktop Dispatch pane: both messages appear, each marked ✓ Read, with a thinking spinner that never resolves. Outputs panel stays empty.

Claude Model

Opus

Is this a regression?

No, this never worked

Last Working Version

_No response_

Claude Code Version

Claude 1.3883.0.0 Claude_pzs8sxrjxfjjc

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Windows Terminal

Additional Information

• Performed full uninstall/reinstall of both Desktop and Android apps before this repro — local state is fresh.
• Normal Chat and standard Cowork sessions work correctly; the failure is isolated to Dispatch response delivery.
• Same symptom pattern as #40179's diagnosis: backend generates response, relay layer between CCR and clients fails to deliver.