* Incremental work on WorkflowStateSerializer
* Update Flow HTTP Request activity to default to Done outcome
* Fix reference handling
* Fix polymorphic object converter
* Add comments
* Add support for registering type alias during DI setup via options
* Fix trigger and bookmark payload persistence
* Update sample model
* Add support for custom dictionary types
* Split general serializer options provider into focused serializer services
* Formatting
* Update migrations
* Import publish execute integration test
* Update test
* Extracted import logic into WorkflowDefinitionImporter
* Removed the WorkflowDefinitionRequest model and done a model rename
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Co-authored-by: Sipke Schoorstra <sipkeschoorstra@outlook.com>