Markdown checkmark not visible when using darkmode

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Describe the bug
Markdown check marks are not visible when using dark-mode which makes it impossible to determine if the item was completed or not.

To Reproduce
Steps to reproduce the behavior:

1. Enable Dark mode in settings
2. Create a note with check marks:

- [ ] text1
- [ ] text2

4. Open note in view mode

Expected behavior
Check mark should be colored white like the text and in the preview when using dark mode.

Screenshots
Preview is working as expected:

Note in View only mode:

Note that the check mark box is barely visible.

Smartphone (please complete the following information):

• Nextcloud Notes-Version (android app): 4.0.0
• F-Droid or Play Store: F-Droid
• Android-Version: 11
• Device: Mi 9T

Server

• Nextcloud version: 25.0.6
• Nextcloud Notes version (server app): 4.7.2

Reproduce the issue in the Android app by enabling dark mode, creating a note with Markdown check marks, and opening it in view-only mode. Compare that rendering with the working preview and trace the dark-mode styling for the checkmark box. Done means the checkmark is clearly visible in view-only mode while preserving the existing preview behavior.