Add transformation to exclude shapes based on ShapeType

[michael-mml]

Add a new transformation to support excluding shapes based on their ShapeType.

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[mtdowling]

What's the use case for this?

[michael-mml]

Our data model is populated from a variety of sources and clients are only interested in the data model itself, they do not care about the services, errors, or operations defined in our Smithy model. This transformation makes it easier to filter these out in a projection rather than tagging the unwanted shapes and using ExcludeShapesByTag transformation.

[mtdowling]

I think we should add a transforms called ExcludeShapesBySelector and IncludeShapesBySelector, which would allow us to use Smithy selectors to filter out or include shapes based on type, traits, members, and more complex logic. For example, you could exclude by type using :is(service, operation). You could exclude shapes that aren't part of a specific service closure using :not([id=some.id#Service] ~> *). We could potentially make existing related transforms just wrappers around the selector based transform (e.g., ExcludeShapeByTrait).

[sugmanue]

A more general approach was implemented in this PR. You can look at the docs for how to do either inclusion or exclusion of shapes using a selector.