For large instances users need to know whether share recipient has Nextcloud account or not

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Is your feature request related to a problem? Please describe.
In commit ae854e0dd2c52693e9c5257141710d9c0f1f8276, the previously combined input field for internal and external shares has been split into two separate input fields.

In a large company with many employees, some of whom are external project team members with accounts in the Nextcloud instance, the problem now arises that users need to know whether the person they want to share something with has an account or not.

Users who are unaware of this will be confused if they enter an external email address in the lower field and receive the message "no elements found".

I've searched through all the issues and haven't found anything related to this: Is anyone else experiencing this problem, or does anyone have any ideas on how to solve it?

Describe the solution you'd like
It would be great if there were a option to have only one input field as before, or to have both input fields recognize internal accounts as well as external email addresses and display them in the correct area after adding them.

The issue references commit ae854e0dd2c52693e9c5257141710d9c0f1f8276; start by examining the split internal and external share inputs and the sharing UI entry point. Determine how the recipient search distinguishes account holders from external email addresses, then verify that the chosen unified or separate-field behavior presents both correctly.