Add project structure tree visualization to components view (#402)

* feat(dashboard): organize My Components as real project structure with .claude/ tree

Replaces the flat type-grouped view in the collections sidebar with a
realistic project directory tree showing exactly how components will be
installed:

  project/
  ├── .claude/
  │   ├── agents/
  │   ├── commands/
  │   ├── skills/
  │   ├── hooks/
  │   └── settings.json
  └── .mcp.json

Adds an ASCII project structure preview in the main content area so
users can visualize the full installation layout before running the
install command.

https://claude.ai/code/session_01Gh8sj2GFiXotit4qSftpid

* Update dashboard/src/components/MyComponentsView.tsx

Co-authored-by: cubic-dev-ai[bot] <191113872+cubic-dev-ai[bot]@users.noreply.github.com>

---------

Co-authored-by: Claude <noreply@anthropic.com>
Co-authored-by: cubic-dev-ai[bot] <191113872+cubic-dev-ai[bot]@users.noreply.github.com>

Author: 3 people