Video question type - recording implementation

### Description

Implement the `video` question type ([specs](https://docs.getodk.org/form-question-types/#video-widgets)). This implementation focuses on enabling video recording via the device camera and external applications.

Technical research required:

* **Video quality control:** Investigate the feasibility of a `video-quality` appearance (similar to `audio-quality`) to provide presets like `low`, `normal`, and `high` for managing file size.
* **Background recording:** Research implementation of the `background` appearance to allow continuous video capture while navigating the form.
* **Widget interface:** Explore options for a standard interface with integrated controls for recording, playback, and replacement

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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?**
- [x] Yes. Specify the endpoints, methods, or data structures needed.
- [ ] No
- **Does it need design around state flow?**
- [ ] Yes. Outline the state flow requirements.
- [ ] No
- **Does it need a test plan?**
- [x] Yes. Add the test plan as a comment in this task or attach the document.
- [ ] No
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### User Stories

* As a data collector, I want to record video directly within the form so that I can provide visual evidence for my observations.
* As a form designer, I want to set video quality levels to optimize data usage for different connectivity environments (pending research).
* As a researcher, I want to enable background video recording to capture the interview context automatically (pending research).
* As a user, I want to preview recorded video within the widget to ensure it is clear and relevant before submitting the form.

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### Design

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

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### Related Issues

- https://github.com/getodk/web-forms/issues/702

No implementation files, tests, or entry points are named. Start by reviewing the ODK video question specification and related issue 702, then clarify the UI/UX, API, quality, background-recording, and test-plan requirements; done means those decisions are documented and the recording, playback, replacement, and external-application flows are implemented and tested.

Written by the indexing model from the issue text.