fix(marketplace): point the Claude plugin source at plugins/conductor

[Aditya Nikam (adityaanikam)]

Fixes #587.

/plugin install conductor@conductor fails in Claude Code with Source path does not exist: <marketplace>/conductor, even though claude plugin marketplace add microsoft/conductor works and claude plugin validate passes.

.claude-plugin/marketplace.json set metadata.pluginRoot to ./plugins and the entry's source to ./conductor. Claude Code resolves a relative source from the marketplace root, and pluginRoot only applies to bare names such as "conductor", not to a source that starts with ./. So the entry pointed at <repo>/conductor, but the plugin lives at <repo>/plugins/conductor. The pluginRoot plus ./name form is the convention the .github/plugin catalog uses, which src/conductor/plugins/marketplace.py already documents.

This changes the source to ./plugins/conductor and removes the pluginRoot setting, which nothing used. A source relative to the repository root works on every Claude Code version, whereas a bare name would need 2.1.239 or later. Conductor's own marketplace reader tries the repository root first, so it still resolves the plugin.

I also added TestShippedMarketplace, which checks that each source in the shipped Claude catalog is a plugin root under the repository root, and a changelog.d/587.fixed.md fragment.

How I checked

On Windows with Claude Code 2.1.229:

• Before the change, claude plugin marketplace add <clone> succeeded and claude plugin install conductor@conductor failed with Source path does not exist: <clone>\conductor.
• After the change, claude plugin marketplace update conductor and the same install succeed, and claude plugin list shows conductor@conductor as enabled.
• The new test fails on the old marketplace.json (conductor: ./conductor) and passes on the new one.
• uv run pytest tests/test_plugins tests/test_cli/test_plugin_commands.py: 463 passed, 12 skipped.
• uv run ruff check src tests and uv run ruff format --check src tests are clean.

I did not test /plugin install from the GitHub repository itself, because that needs this change to be merged first. I also did not test Copilot CLI, which installs with gh skill install and does not read this file.

[Copilot]

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[Codecov Comments Bot (codecov-commenter)]

Codecov Report

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Additional details and impacted files

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  Misses          ?     2356           
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[Jason Robert (jrob5756)]

LGTM, thanks for pointing the Claude plugin source at plugins/conductor!