[ai] Add claude plugins folder in the repo, and setup local plugins and marketplace for repo

[TheLarkInn]

• Add https://github.com/flora131/atomic Claude Code plugin as a local plugin under claude-plugins/atomic-workflow-plugin/
• Replace generic template CLAUDE.md with Rush Stack-specific project instructions (monorepo structure, build commands, code conventions, verification steps, progressive disclosure)
• Add .mcp.json with DeepWiki MCP server configuration
• Simplify .claude/settings.json: remove telemetry hook, remove remote marketplace reference, point to local plugin directory instead
• Remove .claude/hooks/telemetry-stop.ts (telemetry tracking hook no longer needed)
• Move all Atomic agents, commands, and skills from .claude/ into the plugin directory structure (claude-plugins/atomic-workflow-plugin/)
• Add specs/ and research/ to .gitignore for Atomic workflow artifacts
• Include example research docs generated by the Atomic workflow (research/docs/)
• This should also be supported by copilot cli as well

[octogonz]

Seems like this should be installed from a service, like NPM packages, rather than copy+pasted into each repo.

[octogonz]

Is there a way to configure these agentic features in a vendor-netural way?

For example, @L-Qun and I recently were proposing to deprecate Rush's vendor-specific context files and replace it with AGENTS.md + skills in a vendor-netural folder.

The concern is that:

1. There more and more agents every day, it's unrealistic to support them all.
2. The "formats" are all just markdown files that any LLM can understand easily. Besides vendor lock-in, there doesn't seem to be compelling technical justification for vendor-specific plugins.