[BUG] Claude stores absolute paths in known_marketplaces.json

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?

Claude stores absolute paths in known_marketplaces.json (and installed_plugins.json), but those paths break when the .claude directory is mounted accross environments (e.g. into a devcontainer) with a different home directory.

What Should Happen?

Claude should use $HOME-relative paths or resolve them at runtime.

Error Messages/Logs

Plugin Errors                                                                                                                                             
  └ 1 plugin error(s) detected:                                                                                                                             
    └ superpowers@claude-plugins-official: Plugin superpowers not found in marketplace claude-plugins-official`

Steps to Reproduce

Assume settings a devcontainer environment with /home/node/.claude mounted to host /home/user/.claude:

1. Start a devcontainer with user node,
2. Install a plugin using /plugin,
3. Start a devcontainer with user vscode,
4. Install another plugin using /plugin,
5. Run /reload-plugins.

Claude Model

None

Is this a regression?

No, this never worked

Last Working Version

_No response_

Claude Code Version

2.1.81 (Claude Code)

Platform

Anthropic API

Operating System

Ubuntu/Debian Linux

Terminal/Shell

WSL (Windows Subsystem for Linux)

Additional Information

<img width="1718" height="185" alt="Image" src="https://github.com/user-attachments/assets/8080f76a-9487-4dea-8db1-c1c5432f6472" />