legacy UI (#4612)

# Description of Changes

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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)

### 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: Claude <[email protected]>
Co-authored-by: EthanHealy01 <[email protected]>
Co-authored-by: EthanHealy01 <[email protected]>

frontend/src/constants/convertSupportedFornats.ts

@@ -0,0 +1,21 @@
+// Central list of formats supported by Convert operations
+export const CONVERT_SUPPORTED_FORMATS = [
+  // Microsoft Office
+  'doc', 'docx', 'dot', 'dotx', 'csv', 'xls', 'xlsx', 'xlt', 'xltx', 'slk', 'dif', 'ppt', 'pptx',
+  // OpenDocument
+  'odt', 'ott', 'ods', 'ots', 'odp', 'otp', 'odg', 'otg',
+  // Text formats
+  'txt', 'text', 'xml', 'rtf', 'html', 'lwp', 'md',
+  // Images
+  'bmp', 'gif', 'jpeg', 'jpg', 'png', 'tif', 'tiff', 'pbm', 'pgm', 'ppm', 'ras', 'xbm', 'xpm', 'svg', 'svm', 'wmf', 'webp',
+  // StarOffice
+  'sda', 'sdc', 'sdd', 'sdw', 'stc', 'std', 'sti', 'stw', 'sxd', 'sxg', 'sxi', 'sxw',
+  // Email formats
+  'eml',
+  // Archive formats
+  'zip',
+  // Other
+  'dbf', 'fods', 'vsd', 'vor', 'vor3', 'vor4', 'uop', 'pct', 'ps', 'pdf',
+];
+
+