Update the existing date/time property editor to provide a kind of unspecified

[lauraneto]

When requesting a value from the existing date/time property editor, the returned DateTime will now have Kind set to Unspecified instead of Utc.

Testing

1. Create a document type with template, allowed at root, with a property using a Umbraco.DateTime property editor.
2. Create and publish a node using the created document type and set a value in the date field.

Code

1. Adjust the document type template to:

@inherits Umbraco.Cms.Web.Common.Views.UmbracoViewPage
@{
    Layout = null;
    var date = Model.Value<DateTime>("date");
}

@date (@date.Kind)

2. Access the url of the node

Before the changes:1/1/2026 6:02:00 AM (Utc)
After the changes: 1/1/2026 6:02:00 AM (Unspecified)

Delivery API

1. Enable the Delivery API.
2. Request the content node from the delivery API.
   Example: https://localhost:44331/umbraco/delivery/api/v2/content/item/%2F?fields=properties%5B%24all%5D

Before the changes:2026-01-01T06:02:00Z
After the changes: 2026-01-01T06:02:00

[Copilot]

Pull Request Overview

This PR updates the DateTime property editor value converter to return DateTime values with DateTimeKind.Unspecified instead of DateTimeKind.Utc. This change affects how DateTime values are interpreted both in Razor templates and the Delivery API, removing the UTC timezone assumption from returned values.

• Modified the ParseDateTimeValue method to explicitly set DateTimeKind.Unspecified on all returned DateTime values
• Refactored the method logic to use pattern matching for cleaner conditional flow
• Maintained the same fallback behavior of returning DateTime.MinValue for invalid inputs

[AndyButland]

Code all looks good and can see from the unit tests and checks on template rendering and delivery API that the output is as expected.