Remove read only from forms (#3423)

# Description of Changes

Create new tool to remove read-only properties of form fields.

- Added new html file to provide a page for the tool
(misc/unlock-pdf-forms.html), as well as new endpoint
(/unlock-pdf-forms) under config/EndpointConfiguration.java
- Added the tool to the list of "view & edit" tools under the home page
in home-legacy.html and navElements.html
- Mapped the frontend in controller/web/OtherWebController.java
- Created a new controller
(controller/api/misc/UnlockPDFFormsController.java) to handle AcroForm
/Ff flags, /Lock tags and XFA Forms, removing the read-only properties
of all form fields of a PDF document.
- Added language entries to all the language files, to correctly display
the tool's title, header,description, etc.

Closes #2965

---

## Checklist

### General

- [x] I have read the [Contribution
Guidelines](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/CONTRIBUTING.md)
- [x] I have read the [Stirling-PDF Developer
Guide](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/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/HowToAddNewLanguage.md)
(if applicable)
- [x] I have performed a self-review of my own code
- [x] 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/HowToAddNewLanguage.md#add-new-translation-tags)
(for new translation tags only)

### UI Changes

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


![image](https://github.com/user-attachments/assets/2890d3c0-0535-487c-aa0a-83ad9597d898)

![image](https://github.com/user-attachments/assets/631e729c-d68d-4da9-b925-64b5362aeea4)

![image](https://github.com/user-attachments/assets/376a98d5-ca1d-45e9-910f-b5c7639eae8c)



### Testing (if applicable)

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

---------

Co-authored-by: Anthony Stirling <[email protected]>

src/main/resources/messages_en_GB.properties

@@ -364,6 +364,9 @@ home.compressPdfs.title=Compress
 home.compressPdfs.desc=Compress PDFs to reduce their file size.
 compressPdfs.tags=squish,small,tiny
 
+home.unlockPDFForms.title=Unlock PDF Forms
+home.unlockPDFForms.desc=Remove read-only property of form fields in a PDF document.
+unlockPDFForms.tags=remove,delete,form,field,readonly
 
 home.changeMetadata.title=Change Metadata
 home.changeMetadata.desc=Change/Remove/Add metadata from a PDF document
@@ -377,7 +380,6 @@ home.ocr.title=OCR / Cleanup scans
 home.ocr.desc=Cleanup scans and detects text from images within a PDF and re-adds it as text.
 ocr.tags=recognition,text,image,scan,read,identify,detection,editable
 
-
 home.extractImages.title=Extract Images
 home.extractImages.desc=Extracts all images from a PDF and saves them to zip
 extractImages.tags=picture,photo,save,archive,zip,capture,grab
@@ -1193,6 +1195,10 @@ changeMetadata.selectText.4=Other Metadata:
 changeMetadata.selectText.5=Add Custom Metadata Entry
 changeMetadata.submit=Change
 
+#unlockPDFForms
+unlockPDFForms.title=Remove Read-Only from Form Fields
+unlockPDFForms.header=Unlock PDF Forms
+unlockPDFForms.submit=Remove
 
 #pdfToPDFA
 pdfToPDFA.title=PDF To PDF/A