HTMl escape issue

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### Steps to reproduce
1. Subscribe to this atom feed: https://shkspr.mobi/blog/feed/atom/
2. Open the latest article (Esoteric HTML) in the app

### Expected behaviour
The article should display correctly

### Actual behaviour

The `` text is interpreted as an element

https://github.com/user-attachments/assets/7356ef45-dbf1-42df-b3e0-09c0648b3dcc

### Server configuration

**Nextcloud version:** 32.0.12

**Nextcloud news version:** 28.7.0

**Android app version:** 0.9.9.96

Reproduce the issue in the Android app using the Atom feed at https://shkspr.mobi/blog/feed/atom/ and open the latest “Esoteric HTML” article. Trace the article rendering path to find where the text is interpreted, then verify that the article displays it as text rather than an element.

Written by the indexing model from the issue text.