[BUG] VS Code sidebar crashes with Bun v1.3.10 panic on Windows 11 - "integer does not fit in destination type"

Bug Description

Claude Code VS Code extension sidebar consistently crashes on startup with Bun runtime panic. The CLI terminal works perfectly on the same machine.

Error Log

Bun v1.3.10 (1423d3c8) Windows x64 (baseline)
Windows v.win11_dt
CPU: sse42 avx avx2

panic(main thread): integer does not fit in destination type
oh no: Bun has crashed. This indicates a bug in Bun, not your code.

https://bun.report/1.3.10/e_11423d3cEugggC6sg/d61/1nBmk8k0Bqu92M___A0eNoFwcENACAMAsBVWM1ENHyosXzc3js53LyYxYYrWApkTHbkEZWRd/gBNAAPKQ

Extension log shows:

[error] Failed to load config cache: Error: Query closed before response received
[error] Error from Claude (on channel ...): Error: Claude Code process exited with code 3

Environment

• OS: Windows 11 Pro 10.0.26100
• VS Code: 1.109.5 (x64)
• Claude Code Extension: 2.1.49
• Claude Code CLI: 2.1.49
• Bun (bundled): v1.3.10
• RAM: 34 GB
• CPU: SSE4.2, AVX, AVX2

Steps to Reproduce

1. Install Claude Code extension v2.1.49 on VS Code (Windows 11)
2. Open VS Code
3. Click Claude Code sidebar panel
4. Extension spawns Claude process → Bun immediately crashes with panic

Behavior

• Sidebar webview: Always crashes (Bun panic on every spawn attempt)
• CLI terminal (claude command): Works perfectly on the same machine
• Crash is 100% reproducible - happens every single time the sidebar tries to launch

Additional Context

• Confirmed this is not related to MCP server configuration
• Restarting VS Code does not help
• Reinstalling the extension does not help
• The crash report URL has been submitted to Bun: https://bun.report/1.3.10/e_11423d3cEugggC6sg/d61/1nBmk8k0Bqu92M___A0eNoFwcENACAMAsBVWM1ENHyosXzc3js53LyYxYYrWApkTHbkEZWRd/gBNAAPKQ

Related Issues

• #18567
• #19439
• #19666

These issues report the same Bun crash but were filed against older versions. The bug persists in v2.1.49 with Bun v1.3.10.