[V2] refactor(ui): replace native inputs with Mantine components (#4898)

# Description of Changes

#### Before
<img width="779" height="768" alt="image"
src="https://github.com/user-attachments/assets/a6d63bac-e27d-4bd8-b44e-fa72333f4c59"
/>


#### After
<img width="779" height="768" alt="image"
src="https://github.com/user-attachments/assets/f39d8d92-802a-40ff-a7db-2b6a187b6847"
/>


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Please provide a summary of the changes, including:

- What was changed
- Why the change was made
- Any challenges encountered

Closes #(issue_number)
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---

## Checklist

### General

- [ ] I have read the [Contribution
Guidelines](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/CONTRIBUTING.md)
- [ ] I have read the [Stirling-PDF Developer
Guide](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/devGuide/DeveloperGuide.md)
(if applicable)
- [ ] I have read the [How to add new languages to
Stirling-PDF](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/devGuide/HowToAddNewLanguage.md)
(if applicable)
- [ ] I have performed a self-review of my own code
- [ ] My changes generate no new warnings

### Documentation

- [ ] I have updated relevant docs on [Stirling-PDF's doc
repo](https://github.com/Stirling-Tools/Stirling-Tools.github.io/blob/main/docs/)
(if functionality has heavily changed)
- [ ] I have read the section [Add New Translation
Tags](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/devGuide/HowToAddNewLanguage.md#add-new-translation-tags)
(for new translation tags only)

### Translations (if applicable)

- [ ] I ran
[`scripts/counter_translation.py`](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/docs/counter_translation.md)

### UI Changes (if applicable)

- [ ] Screenshots or videos demonstrating the UI changes are attached
(e.g., as comments or direct attachments in the PR)

### Testing (if applicable)

- [ ] I have tested my changes locally. Refer to the [Testing
Guide](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/devGuide/DeveloperGuide.md#6-testing)
for more details.

---------

Signed-off-by: Balázs Szücs <[email protected]>
Co-authored-by: Reece Browne <[email protected]>

frontend/public/locales/en-GB/translation.toml

@@ -3800,6 +3800,11 @@ failed = "An error occurred while compressing the PDF."
 _value = "Compression Settings"
 1 = "1-3 PDF compression,</br> 4-6 lite image compression,</br> 7-9 intense image compression Will dramatically reduce image quality"
 
+[compress.compressionLevel]
+range1to3 = "Lower values preserve quality but result in larger files"
+range4to6 = "Medium compression with moderate quality reduction"
+range7to9 = "Higher values reduce file size significantly but may reduce image clarity"
+
 [decrypt]
 passwordPrompt = "This file is password-protected. Please enter the password:"
 cancelled = "Operation cancelled for PDF: {0}"