[BUG] Path construction bug on Windows with UNC paths - prevents access to conversation history

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?

Bug Report Draft

Title

Path construction bug on Windows with UNC paths - prevents access to conversation history

Environment

• OS: Windows
• Extension: Claude Code VS Code Extension
• Workspace Path: \\diskstation\docker\ (UNC network path)
• Config Directory: C:\Users\Patrick\.claude\

Description

The extension has a path construction bug when using Windows UNC workspace paths, causing two critical issues:

Error Message:

ENOENT: no such file or directory, scandir 'C:\Users\Patrick.claude\projects--diskstation-docker'

Issue #1: Missing Backslash
The extension constructs the path with a missing backslash:

• Constructed: C:\Users\Patrick.claude\projects--diskstation-docker
• Should be: C:\Users\Patrick\.claude\projects\--diskstation-docker-

Notice the missing \ between Patrick and .claude.

Issue #2: Incorrect Path Joining
The extension concatenates path segments instead of joining them:

• Actual directory: C:\Users\Patrick\.claude\projects\--diskstation-docker-\
• Extension looks for: C:\Users\Patrick.claude\projects--diskstation-docker

The extension appears to:

1. Concatenate "projects" with the encoded workspace name
2. Use string concatenation instead of proper path joining

Impact

• Past conversations exist but are not accessible via the extension UI
• Extension cannot read/write conversation history properly
• Plans not displayed in extension sidebar
• All conversation history is orphaned

Actual File System State

C:\Users\Patrick\.claude\projects\--diskstation-docker-\
├── 1acbd671-b412-4bdc-bb00-a09bb94c0aef.jsonl (1MB)
├── 3ca7f301-c152-4bb4-a075-944adfdf6406.jsonl (33KB)
├── 8eb811d7-a26d-4f41-ab6b-64a4e54fce71.jsonl (20KB)
└── [30+ more conversation files]

All these files are inaccessible to the extension.

Suggested Fix Location

Likely in the extension's:

• Config directory resolution logic
• Project directory naming/encoding
• Path joining utilities (replace string concat with path.join())

What Should Happen?

Expected Behavior

The extension should:

1. Use proper Windows path separators when constructing .claude directory paths
2. Join path segments using path.join() instead of string concatenation
3. Correctly handle Windows UNC paths

Error Messages/Logs

**Error shown**: `ENOENT: no such file or directory, scandir 'C:\Users\Patrick.claude\projects--diskstation-docker'`

Steps to Reproduce

Reproduction

1. Open VS Code on Windows
2. Open a workspace on a UNC network path (e.g., \\servername\share\)
3. Use Claude Code extension
4. Check extension logs for ENOENT errors
5. Verify conversation history is not displayed in sidebar

Claude Model

Sonnet (default)

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

anthropic.claude-code 2.0.73

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

VS Code integrated terminal

Additional Information

!Image