Show uploaded filename on file widget

### Description

Filenames are changed on upload which reduces conflicts. However it's confusing to users who expect to see the file name that they selected to confirm they picked the right file.

Update the upload widgets to show the uploaded file name as well as the generated file name.

During submission the uploaded filename is discarded, so when editing only show the generated file name.

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### Checklist
- **Does it need UI/UX design?**
- [x] Yes. Describe the UI/UX requirements or attach a Figma link in the "Design" section.
- [ ] No
- **Does it need API design?**
- [ ] Yes. Specify the endpoints, methods, or data structures needed.
- [x] No
- **Does it need design around state flow?**
- [ ] Yes. Outline the state flow requirements.
- [x] No
- **Does it need a test plan?**
- [ ] Yes. Add the test plan as a comment in this task or attach the document.
- [x] No
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### User Stories

- **As a** form jockey,
**I want** to see the name of the file I just uploaded,
**so that** I can be confident I uploaded the right thing.

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### Design

- **Figma**: [Insert URL]
- **Design Docs**: [Insert URL]

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### Dependencies

-

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### Additional Notes

-

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### Related Issues

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No files, tests, or design assets are named. Start by locating the upload widgets and the submission/editing state that supplies their displayed filenames. Done means a newly uploaded file shows both its selected filename and generated filename, while editing shows only the generated filename.

Written by the indexing model from the issue text.