Some Restock & Price Detection helper texts are not translatable

**Describe the bug**
Several helper texts in the “Restock & Price Detection” section are not translatable.

The field labels in this section are correctly translated, but several explanatory/helper texts are always displayed in English when using the Polish translation.

The affected texts are:

- “Changes in price should trigger a notification”
- “Minimum amount, Trigger a change/notification when the price drops below this value.”
- “Maximum amount, Trigger a change/notification when the price rises above this value.”
- “Price must change more than this % since the previous check to trigger a change.”
- “For example, if the previous check saw the product at $1,000 USD, 2% would mean it has to change more than $20 since then.”
- “Note! A Group tag overrides the restock and price detection here.”

The corresponding strings appear to be hardcoded in `changedetectionio/processors/restock_diff/forms.py` instead of being wrapped in gettext, so they are not available in the translation catalog.

**Version**
0.60.3

**How did you install?**

Docker

**To Reproduce**

Steps to reproduce the behavior:
1. Set the application language to Polish.
2. Open or create a watch.
3. Open the “Restock & Price Detection” section.
4. Notice that the field labels are translated, but the explanatory/helper texts remain in English.

**Expected behavior**
All user-facing texts in the “Restock & Price Detection” section should be translatable and displayed in the selected language.

**Additional context**
The Polish translation itself appears to be working correctly. Other translated strings in the same section are displayed in Polish.

This seems to be caused by the strings not being passed through gettext rather than by a missing Polish translation.

I noticed this while using the newly released 0.60.3, which also introduces support for local translation overlays.