[FR] Option to set `Default language` and `Encoding`

### Description

In NPP++, you can set both;

- Default lang: [ options here ] <--- will apply this for each newly opened tab by default
- Encoding: UTF-8, UTF-8 with BOM, ANSI, UCS-2BE, etc

### Describe the solution you'd like

_No response_

### Describe alternatives you've considered

_No response_