feature: default values for user-defined PostCreateHook variables

[MikeSpreitzer]

Feature Description

A PostCreateHook should be able to define default values for its user-defined variables.

Proposed Solution

Add a way to do that.

Want to contribute?

• I would like to work on this issue.

Additional Context

No response

[pdettori]

@MikeSpreitzer this sounds like an useful feature, any thoughts on where such default values could be maintained ?

[MikeSpreitzer]

The idea that first comes to mind is adding a section in the PostCreateHook object. The simplest schema would be a map from variable name to default value. The recommended pattern in Kubernetes is to eschew such simplicity for the sake of making the domain of every map fixed in the schema, instead using a list of (name, value) pairs.