Improve text editor performance

### Please agree to the following

- [x] I have searched [existing issues](https://github.com/cryptomator/android/issues?q=) for duplicates
- [x] I agree to follow this project's [Code of Conduct](https://github.com/cryptomator/android/blob/develop/.github/CODE_OF_CONDUCT.md)

### Summary

Improve text editor performance

### Motivation

Once a text file contains a few thousand lines (Yes, it's about line breaks. Large amounts of text without line breaks aren't a problem.), writing text becomes pretty sluggish. Although, I suppose overall, it depends on the device and the keyboard being used. I've attached a file that's slow even on a Tab S9.

[text.txt](https://github.com/user-attachments/files/20371715/text.txt)

### Considered Alternatives

The same file doesn't exhibit bad performance when edited using QuickEdit+, which means that there's something specific to the text editor in Cryptomator.

### Anything else?

Why I care about it: I use Cyptomator as my knowledge database every day. With the internal text editor, it's one tap to open, one tap to save/close. With QuickEdit+, it's two taps to open and three to save/close.