Support for installing packages as Claude Plugins/Google Extensions/etc.

[vegastyle]

Currently when you install a package it gets added straight into the .claude/.gemini/etc. folders. As mentioned before one of the issues is that his creates namespace conflicts and flattens the structure of the packages. The current solution for namespaces is generic but should be able to leverage a tools built-in namespace structure if available. As the cli already supports parsing claude code plugins and extensions to packages it should be able to do the inverse and install them into an appropriate local marketplace for the respective tool to use.

[hyericlee]

Makes sense, will look into this, thanks David!