Fix: Prevent plugins from being installed to wrong type directory (fixes #235)

[swashbuck]

Fixes #235

Fix

• Check installed plugins before determining install targets — fetchProjectInfo() is now called during loadPluginData() so the CLI knows what's already on disk
• Skip plugins that are already installed at the matched version, preventing duplicate installations
• Infer plugin type from the existing install path (e.g. src/menu/adapt-contrib-boxMenu → type menu) before falling back to keyword/attribute detection — this prevents already-installed plugins from being misrouted to the default src/components/ directory

Testing

1. Start with a project where adapt-contrib-boxMenu is installed in src/menu/ and listed in adapt.json with "*"
2. Run adapt install adapt-contrib-media
3. Verify adapt-contrib-boxMenu is NOT duplicated into src/components/
4. Run adapt install (no args) and verify all plugins go to their correct type directories
5. On a clean project, run adapt install adapt-contrib-boxMenu and verify it installs to src/menu/
6. Verify a mix of component/extension/menu/theme plugins all route correctly