Plugin Scope Installation

What: Plugins can now be installed with different scopes: user, project, or local. How to use: When installing a plugin via the UI, you can now choose:

• "Install for you (user scope)" - Available across all projects
• "Install for all collaborators on this repository (project scope)" - Shared via .claude/settings.json
• "Install for you, in this repo only (local scope)" - Local only, not committed

Details:

• Plugin installation now tracks scope in installed_plugins_v2.json
• Supports migration from V1 plugin installation format
• Evidence: _G9() at line 480734, rE() at line 483476, eI9() at line 483520, Ez9() at line 511472