Code blocks should not be wrapped

**Describe the bug**
Code blocks wrap, messing up formatting

**To Reproduce**
1. add code block with long lines
2. phone in portrait mode

**Expected behavior**
Code block displays as-is, adding scrollbar if it gets beyound the viewport.

**Screenshots**

**Smartphone**
- Device: Xperia 10 VI
- OS: Android 15
- App: Voyager 2.47.4

No files or tests are named in the report. Start in the mobile frontend code path that renders post/content markdown and find the stylesheet or component styles for `pre`/`code` blocks. Check small-viewport overflow and white-space behavior, then update it so long lines stay unwrapped and use scrolling instead. Confirm by reproducing the steps on a phone portrait viewport and ensuring code blocks remain on one horizontal line.

Scritto dal modello di indicizzazione a partire dal testo della issue.