Fix#14986
This PR includes some refactoring to simplify the interaction
of the `NodeWorkflow` and the `BaseWorkflow` with the registry.
We were registering redundant `addPostTransform`s. Some of them in
the constructor of the `BaseWorkflow`, which did not allow us to
intercept `addUndefinedDefaults`.
Additionally, we were setting the `validateOptionsWithSchema` transform
multiple times unnecessarily.
An issue left to fix is support for the `--project` option in
schematic commands. Currently, `getProjectName` does not know about
this option, since `createWorkflow` does not know how to parse the
command line arguments. The parsing logic is implemented partially
by the concrete implementation of the `SchematicCommand` template
method.
Schematics context now have an (optional) analytics field that, if set,
should be used to report usage. This can be set even in some cases where
analytics is disabled (to a noop analytics).
