Closes#161002Closes#170073
## Summary
This PR implements a createModelVersion API in the Encrypted Saved
Objects plugin to support upward migrations for model version encrypted
saved objects.
Much like how the `createMigration` API provided a way to wrap migration
functions to support migration of encrypted saved objects prior to the
model version paradigm, the new `createModelVersion` API provides a way
to wrap a model version definition for the same purpose.
`createModelVersion` manipulates the changes defined for a model version
('unsafe_transform', 'data_backfill', 'data_removal'), merging them into
a single transform function in which the saved object document is
decrypted, transformed, and then encrypted again. The document is
decrypted with the `encrypted saved object type registration` provided
by the required `inputType` parameter. Similarly, the document is by
encrypted with the `encrypted saved object type registration` provided
by the required `outputType` parameter.
An example plugin (`examples/eso_model_version_example`) provides a
demonstration of how the createModelVersion API should be used. The UI
of the example plugin gives an idea of what the encrypted saved objects
look like before and after the model version changes are applied.
## Testing
### Manual Testing
- Modify the example plugin implementation in
`examples/eso_model_version_example` to include different changes or
additional model versions.
### Unit Tests
-
`x-pack/plugins/encrypted_saved_objects/server/create_model_version.test.ts`
### Functional Tests
-
`x-pack/test/encrypted_saved_objects_api_integration/tests/encrypted_saved_objects_api.ts`
-
`x-pack/test/encrypted_saved_objects_api_integration/tests/encrypted_saved_objects_decryption.ts`
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Co-authored-by: kibanamachine <42973632+kibanamachine@users.noreply.github.com>
