Support file encoding on a project / subproject basis

### Description

I am not sure if this is a actually a bug, but I think it is more of a feature request.

Under Windows, a file, or files, that are encoded in UTF-8 can't be opened. It would be nice if you could set this on a project basis. I can't even open the repository https://github.com/milg0/onvif-java-lib.git using either Netbeans 12 in regular Windows (or NetBeans 16 under WSL2). The project compiles fine from the command line using Gradle, but I can't open or edit the project in NetBeans.

### Use case/motivation

I would like the UTF-8 project to be opened and compiled in NetBeans.

### Related issues

_No response_

### Are you willing to submit a pull request?

No

Start by reproducing the failure with the onvif-java-lib repository in NetBeans 12 on Windows or NetBeans 16 under WSL2, then trace how NetBeans detects project and subproject file encodings. Done means a UTF-8 project can be opened, edited, and compiled in NetBeans with encoding configurable per project or subproject.

Written by the indexing model from the issue text.