Support an "Update All Local Modules" scenario

We should support the following pattern:

`Get-Module -ListAvailable | Update-ModuleFast`

If we detect a standard module path is provided to us, we should translate that into a modulespec as follows:
1. Versions greater than what was provided up to the next major version
2. Implied -Update in this regard
3. Display "Module Not Found" in the gallery as a warning rather than a hard stop.
4. If -Update is explicitly specified, then the major version restrictions are lifted.

This should probably also come after multi-repo support.

Start with the `Get-Module -ListAvailable | Update-ModuleFast` entry point and trace how a standard module path becomes a modulespec. Check how multi-repo support is handled first, since the issue says this should come afterward. Done means version bounds, implied updates, explicit `-Update` behavior, and gallery "Module Not Found" warnings match all four stated cases.

Vom Indexierungsmodell aus dem Issue-Text verfasst.