fix: correct Russian auto-turn translations (#1566)

## Summary

* **What is the goal of this PR?**
Fix inaccurate Russian UI text for the reader auto-turn feature and make
the affected Russian labels consistent with how adjacent UI strings are
formatted.

* **What changes are included?**
Updated Russian translations in `lib/I18n/translations/russian.yaml`:
- changed `Auto Turn` text from wording that implied screen rotation to
wording that means automatic page turning
- adjusted a few Russian prefix/separator strings to include spacing
where the UI concatenates labels with dynamic values

## Screenshots

| Before| After |
|--------|--------|
| <img width="480" height="800" alt="image"
src="https://github.com/user-attachments/assets/db416dd2-6174-4a46-bd3a-6f52d1cc01cb"
/>| <img width="480" height="800" alt="image"
src="https://github.com/user-attachments/assets/dd9055e0-d4f1-459d-bd40-60fc4970d458"
/>|



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Did you use AI tools to help write this code? _**NO**_

lib/I18n/translations/russian.yaml

@@ -288,5 +288,5 @@ STR_BOOK_S_STYLE: "Стиль книги"
 STR_EMBEDDED_STYLE: "Встроенный стиль"
 STR_OPDS_SERVER_URL: "URL OPDS сервера"
 STR_SCREENSHOT_BUTTON: "Сделать снимок экрана"
-STR_AUTO_TURN_ENABLED: "Авто-поворот включён: "
+STR_AUTO_TURN_ENABLED: "Автоперелистывание: "
-STR_AUTO_TURN_PAGES_PER_MIN: "Авто-поворот (Страниц в минуту)"
+STR_AUTO_TURN_PAGES_PER_MIN: "Автоперелистывание (стр./мин)"