* Adding member types sibling endpoints
* Introducing sibling endpoint for Partial Views and logic.
* Introducing sibling endpoint for stylesheets
* Introducing sibling endpoint for scripts
* Introducing FileSystemTreeServiceBase.cs
* Introducing interfaces for implementation specific services
* Introducing services for specific trees
* Modifying controller bases to fit new interface and logic.
* Obsoleting old constructors related to PartialView
* Obsoleting ctors related to Stylesheets
* Obsoleting ctors related to scripts
* Adding tests for scriptsTreeService
* Adding tests for siblings
* Removing unused dependencies
* Removing signs and replacing it with flags
* Fixing breaking changes by obsoletion
* Fixing more breaking changes
* Registering missing service
* Fixing breaking changes again
* Changing name of method GetSiblingsViewModels
* Rewritten tests for less bloat and less duplicate code
* Expanding tests to include other methods from service
* Test refactoring: avoided populating file systems that weren't under test, updated encapsulation, renaming, further re-use.
* Management API: Expanding the existing sibling endpoints to support trashed entities (#20154)
* Refactoring existing logic to include trashed items
* Including tests for trashed entities
* Groundwork for trashed siblings
* Documents trashed siblings endpoint
* Controller for Media trashed items
* Expanding tests to include a test for trashed siblings
* Code review corrections
* Resolving code review
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Co-authored-by: Andy Butland <abutland73@gmail.com>
* Updated API version package and moved attribute to each controller as it cannot be inherited.
* Ignore "$type" on types implementing interfaces in the delivery api
* Created a common library for the APIs and moved stuff that is required for the new content API. Also moved the versioned backoffice API route handling to the management API where it belongs.
* Remove test auth attribute from Media
