Studio TimePicker inspector should expose Hour/Minute/Second instead of design-time SelectedTime

The Studio visual designer inspector exposes a design-time "SelectedTime" field for TimePicker, but it only preserves hours and minutes. Entering a value with seconds, such as 12:34:56, is accepted as a valid time and is then normalised to 12:34, silently discarding the seconds.

This looks inconsistent with the public TimePicker API, which supports Hour, Minute, and Second, and with the docs listing Second as a read/write property.

Expected behaviour:

Either the designer’s "SelectedTime" inspector field should support seconds and emit .Second during generated setup, or the inspector should make it clear that only HH:mm is supported.

Since the runtime TimePicker.Second property exists, preserving seconds seems like the right fix.

Reproducing:

• Add a TimePicker in the Studio visual designer.
• In the inspector, set SelectedTime to 12:34:56.
• Commit/focus away from the field.
• The value becomes 12:34, losing 56 seconds.