[BUG] VS Code extension v2.1.129 fails to activate on Windows — hardcoded Linux CI path regression

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 VS Code extension v2.1.129 (win32-x64) fails to activate on Windows. The sidebar shows an infinite loading spinner ("Loading sessions...") and all claude-vscode.* commands return "command not found".

This is a regression of the same hardcoded Linux CI build path issue previously reported and fixed in v2.1.51 (#28054, #28056, #28081) and v2.1.55 (#28416).

What Should Happen?

Extension activates successfully on Windows, sidebar loads, and Claude Code commands are available in the Command Palette.

Error Messages/Logs

2026-05-06 17:39:28.854 [info] ExtensionService#_doActivateExtension Anthropic.claude-code, startup: false, activationEvent: 'onView:claudeVSCodeSidebarSecondary'
2026-05-06 17:39:28.949 [error] Activating extension Anthropic.claude-code failed due to an error:
2026-05-06 17:39:28.949 [error] TypeError: The argument 'filename' must be a file URL object, file URL string, or absolute path string. Received 'file:///home/runner/work/claude-cli-internal/claude-cli-internal/build-agent-sdk/sdk.mjs'
	at Module.createRequire (node:internal/modules/cjs/loader:1922:13)
	at Object.<anonymous> (c:\Users\mja\.vscode\extensions\anthropic.claude-code-2.1.129-win32-x64\extension.js:102:5407)


**Environment:**
- OS: Windows 11
- VS Code: Latest
- Node.js: v25.2.1
- Extension version: 2.1.129 (win32-x64)
- Claude CLI: Working independently in terminal

Steps to Reproduce

1. Install Claude Code for VS Code v2.1.129 on Windows
2. Open VS Code
3. Click the Spark icon or run any claude-vscode command

Expected: Extension activates and sidebar loads.
Actual: Infinite spinner, commands not found, extension fails to activate.

Workaround: Rolling back to v2.1.126 resolves the issue. Disable auto-update to prevent re-upgrading.

Root Cause: The extension.js bundle contains a hardcoded file:///home/runner/work/claude-cli-internal/... path from the GitHub Actions CI runner that is invalid on Windows. This is the same root cause as #28054 and #28416 — the build pipeline fix has regressed.

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

2.1.126

Claude Code Version

2.1.81

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

VS Code integrated terminal

Additional Information

_No response_