Describe the suggested improvement
Is your improvement related to a problem? Please describe.
Currently property encryption is limited to string values only. A user can inherit from EncryptedString and use that in its message types but this type results in coupling the message type to a specific version of NServiceBus.Encryption.MessageProperty.
Describe the suggested solution
Extract EncryptedString into a separate interface package similar to NServiceBus.MessageInterfaces so this type can be shared between multiple versions of NServiceBus.Encryption.MessageProperty.
Additional Context
No response