Emits `input` event from <entity-select> on change and reset

What does this MR do and why?

It updates the component to emit input event on selection and on reset, allowing its consumers to listen on that event.

The changes in this MR will be used in !116248 (merged).

Screenshots or screen recordings

N/A

How to set up and validate locally

Numbered steps to set up and validate the change are strongly suggested.

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.

Related to #381681