feat(redaction): improve manual redaction with color selection and updated UI elements (#5679)

# Description of Changes

<img width="1920" height="977" alt="image"
src="https://github.com/user-attachments/assets/17e451b7-df2b-4097-b8aa-66954d89b935"
/>


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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]>

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

@@ -4879,6 +4879,9 @@ applyRedactions = "Apply Redactions"
 applyWarning = "⚠️ Permanent application, cannot be undone and the data underneath will be deleted"
 boxRedaction = "Box draw redaction"
 colourPicker = "Colour Picker"
+colorLabel = "Redaction Colour"
+active = "Redaction Mode Active"
+activate = "Activate Redaction Tool"
 controlsTitle = "Manual Redaction Controls"
 convertPDFToImageLabel = "Convert PDF to PDF-Image (Used to remove text behind the box)"
 export = "Export"