* Fix nullability of Children extension
* Fix nullability of methods throughout the CMS
* Fix return types of some methods that cannot return null
* Revert nullable changes to result of ConvertSourceToIntermediate for property editors (whilst some property editors we know won't return null, it seems more consistent to adhere to the base class and interface nullability definition).
* Updated new webhook events to align with new nullability definitions.
* Reverted content editing service updates to align with base classes.
* Applied collection nullability updates on content repository to interface.
* Reverted value converter updates to match interface.
* Applied further collection updates to interface.
* Aligned media service interface with implementation for nullability.
* Update from code review.
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Co-authored-by: Ivo van der Bruggen <ivo@dutchbreeze.com>
Co-authored-by: Ivo van der Bruggen <ivo@vdbruggensoftware.com>
Co-authored-by: Andy Butland <abutland73@gmail.com>
* Move adding webhooks to extension methods
* Clean up WebhookEventCollectionBuilder
* Rename AddAllAvailableWebhooks to AddCmsWebhooks and internalize defaults
* Use fluent CmsWebhookEventCollectionBuilder for adding CMS specific webhook events
* Split media and media type webhook events
* Use fluent CmsUserWebhookEventCollectionBuilder for adding CMS user specific webhook events
* Rename extension methods and add onlyDefault parameter
* Remove duplicate UserForgotPasswordRequestedWebhookEvent
* Add document type webhook events and use fluent builders for content and content types
* Use fluent WebhookEventCollectionBuilderCmsMember for adding member/member group webhook events
* Use fluent WebhookEventCollectionBuilderCmsTemplate for template/partial view webhook events
* Use fluent WebhookEventCollectionBuilderCmsFile for file based webhook events (instead of only template/partial view)
* Move all webhook events to Umbraco.Cms.Core.Webhooks.Events namespace
* Reorder AddFile method and update documentation
