[BUG] Windows Desktop (MSIX) ships corrupted Claude Code binary

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?

The Windows Desktop app (MSIX) ships a Claude Code binary that is missing its embedded JavaScript bundle. Instead of running Claude Code, claude.exe is a bare Bun runtime — invoking it prints Bun's own help text and reports Bun's version (1.3.13) rather than a Claude Code version. As a result, every Code session crashes immediately with Claude Code process exited with code 1 before any first response.
A full uninstall + reinstall of the Desktop app does not fix it — the freshly installed binary has the same problem.
Chat works normally. Only Code is affected.

<img width="1937" height="1245" alt="Image" src="https://github.com/user-attachments/assets/ba76925d-c4ff-4244-af0c-a575ea32a86c" />

What Should Happen?

Expected Behavior
Code session responds normally.

Actual Behavior
UI shows: Claude Code process exited with code 1
Child process exits in 0 seconds, hadFirstResponse=false, reason=no_response.

Error Messages/Logs

OAuth and session bootstrap succeed; the failure is purely in the spawned child.

[info] Using Claude Code binary at: C:\Users\<user>\AppData\Roaming\Claude\claude-code\2.1.119\claude.exe
[error] Session local_<id> query error: Claude Code process exited with code 1
    at Gdr.getProcessExitError (app.asar\.vite\build\index.js:390:8215)
    at ChildProcess.i (app.asar\.vite\build\index.js:390:11260)
    at ChildProcess._handle.onexit (node:internal/child_process:295:12)
[info] [CCD CycleHealth] unhealthy cycle for local_<id> (0s, hadFirstResponse=false, reason=no_response)

Steps to Reproduce

1. Install Claude Desktop on Windows from claude.com/download (MSIX).
2. Open a new Code session in any directory.
3. Send any prompt (e.g. hey).
4. Session is created and titled (this could be a good diagnosis point) , then immediately fails with Claude Code process exited with code 1.

Claude Model

Opus

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

1.3.13 (incorrectly displayed)

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

PowerShell

Additional Information

Things Already Tried

Full uninstall + reinstall of Claude Desktop — no change.
ANTHROPIC_API_KEY confirmed unset (user and system scopes).
OAuth re-login — succeeds, does not affect the issue.

Suggested Investigation

Verify the integrity of the claude.exe shipped/downloaded by version 1.4758.0.0 of the Windows MSIX build. The binary running on this machine is missing its embedded bundle — either the packaged version is bad, or the post-install download step is producing a stripped artifact (possibly via AV interference with Bun single-file executables, which is a known interaction worth ruling out).
A sha256 of a known-good claude.exe for 2.1.119 would let users verify locally.

Hash on my machine

> Get-FileHash "C:\Users\user\AppData\Roaming\Claude\claude-code\2.1.119\claude.exe" -Algorithm SHA256

Algorithm       Hash                                                                   Path
---------       ----                                                                   ----
SHA256          0F85D99FD94D06436DFDE6088BF0521DDA8B8A77923FC2CE85CD15E74189BFA7       C:\Users\user\AppData\Roaming\Claude\claude-code\2.1.119\claude.exe

Environment

Claude Desktop: 1.4758.0.0 (MSIX: Claude_1.4758.0.0_x64__pzs8sxrjxfjjc)
Bundled Claude Code binary: C:\Users\<user>\AppData\Roaming\Claude\claude-code\2.1.119\claude.exe
OS: Windows (64-bit)
Auth: claude.ai OAuth (working — token cached, session ID issued)
ANTHROPIC_API_KEY: not set
Reinstall performed: yes (no change)