Feature/v2/improve sign (#4627)

# Description of Changes

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Please provide a summary of the changes, including:

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- Why the change was made
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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)

### 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.

---------

Co-authored-by: Copilot <[email protected]>
Co-authored-by: James Brunton <[email protected]>
Co-authored-by: Claude <[email protected]>

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

@@ -1819,8 +1819,16 @@
       "placeholder": "Enter your full name"
     },
     "instructions": {
-      "title": "How to add signature"
+      "title": "How to add signature",
+      "canvas": "After drawing your signature in the canvas, close the modal then click anywhere on the PDF to place it.",
+      "image": "After uploading your signature image above, click anywhere on the PDF to place it.",
+      "text": "After entering your name above, click anywhere on the PDF to place your signature."
     },
+    "mode": {
+      "move": "Move Signature",
+      "place": "Place Signature"
+    },
+    "updateAndPlace": "Update and Place",
     "activate": "Activate Signature Placement",
     "deactivate": "Stop Placing Signatures",
     "results": {