* Force system text json for IJSonSerializer
* Migrate ColorPickerValueConverter
* Move ColorPickerValueConverter
* Clean up ColorPickerValueConverter
* Remove obsoleted property editors
* Migrate FlexibleDropdownPropertyValueConverter to System.Text.Json
* Use IJsonSerializer instead and move the value converter to Core
* Migrate ImageCropperValueConverter to System.Text.Json
* Inject jsonserializer in test and obsolete old constructor
* Migrate JsonValueConverter to System.Text.Json
* Remove ContextualConfigurationEditorJsonSerializer
* Remove JsonNetSerializer
* Remove obsolete DeserializeSubset from JsonSerializer interface
* Fix FlexibleDropdownPropertyValueConverter
* Update test JSON to be actual valid json
* Update more test json
* Update time format to be valid
* Add JsonPropertyName to models
* Property level validation for content - initial implementation
* Always succeed create/update regardless of property level validation errors
* Move old complex editor validation classes to Web.BackOffice so they will be deleted
* Include operation status and property validation errors in ProblemDetails
* Refactor property validation to its own service(s)
* Make the problem details builder a little more generic towards extensions
* Validation for item and branch publish
* Moved malplaced test
* Get rid of a TODO
* Integration tests for content validation service
* Simplify validation service
* Add missing response types to create and update for document and media
* Remove test that no longer applies
* Use "errors" for model validation errors (property validation errors)
* Split create/update and validation into their own endpoints
* Fix forward merge
* Correct wrong assumption for missing properties
* Remove localization from validation error messages - decreases dependencies, adds a lot of obsolete constructors
* Reuse existing validation service + support custom error messages
* Fix merge errors
* Review comments
* Moved refactor from V12 based branch
* Remove obsolete config property to avoid obsoletion warnings
* Clean up test models
* Make the datatype API a little less confusing by introducing explicit models for create and update
* Remame "Configuration" to "Data" to make FE happy :)
* Safeguard deserialization of empty configs
* Less strict number handling for deserialization
* Prepare for data type config migrations
* Attempt to have contextual config serializers
* Update OpenAPI spec with (temporary) data type controller
* Fix unit tests
* Update compat suppressions (allow breakage for datatype and configuration editor)
* Make the duplicate JsonObjectConverter implementation private
