Better feedback when person has already been shared with

In scenarios such as:

A recipient trying to re-share a file with the original owner.

Attempting to create a duplicate share with a user who already has access.

Instead of blocking the action with an error or hiding the user from the search results, show a message in the search dropdown like:

**Already shared with this user**

This approach provides a more positive and informative user experience, replacing error messages with clear feedback.