feat(webcams): add iframe-based webcam service option

[justinh-rahb]

Description

This PR adds an optional iframe-based webcam service that allows embedding arbitrary webpages as webcam tiles.

Mainsail currently assumes webcams are video streams (MJPEG/WebRTC). This works well for traditional cameras, but makes it impossible to display non-video visual sources that are exposed as webpages.

The iframe service is fully opt-in, isolated from existing webcam implementations, and easy to ignore for setups that don’t need it.

Concrete use case

On Snapmaker U1 (Extended community firmware), the printer exposes a live, interactive view of its integrated touchscreen as a webpage rather than a video stream.

With iframe webcam support:

• A print is sent from Orca
• Orca switches to the Device tab
• The printer's screen UI is embedded directly in Mainsail
• Spool and print options can be confirmed immediately
• No Snapmaker Orca Device tab or mobile app is required

A short recording demonstrating this workflow is included below.

What’s included

• New iframe-based webcam streamer integrated into existing lazy-loading and rendering logic
• New Webpage (iframe) webcam service option in settings
• Aspect-ratio–based responsive sizing with validation and inline guidance
• Default aspect ratio of 16:9 for new iframe webcams
• Updated webcam type definitions to include iframe configuration
• English locale strings for iframe-specific labels and validation feedback

Scope

• Fully opt-in via a new webcam service type
• No changes to existing webcam behavior
• No assumptions about the embedded page (static or interactive)
• Intended to be ignored by users who only use traditional webcams

Related Tickets & Documents

Mobile & Desktop Screenshots/Recordings

Screen.Recording.2026-01-09.at.10.26.39.AM.mp4

[meteyou]

This is exactly the Webcam mode which I don't want to implement, because it could be "miss used" like that...

I will review the code and see if there are some "downsides" of it.

[justinh-rahb]

Totally fair — I understand the concern.

All I can really ask is that you consider it on its technical merits. It’s fully opt-in, isolated, and doesn’t affect existing webcam behavior.

For me it solves a real use case right now, and keeping it upstream would avoid having to maintain a long-term patch or fork for something that’s otherwise generic and self-contained.

Happy to tighten or constrain it if you spot concrete downsides during review.

[meteyou]

@justinh-rahb pls enable "Allow edits by maintainers" in the sidebar. I just fixed the rotation and make the aspectRatio more generic, because I should add this also for other streamers.

[justinh-rahb]

@meteyou just enabled it. thanks for taking a look and for the improvements.

Happy to help or adjust anything else as needed.

[meteyou]

@justinh-rahb thx! i pushed my changed. pls double check it again, then i will merge it.

[justinh-rahb]

@meteyou looks good to me 👍
I’m spinning up a test build on my U1 right now and will report back shortly.

[meteyou]

@justinh-rahb did you disabled the option to push commits again?

I just would like to push a small fix for the aspect ratio validation.

[justinh-rahb]

@justinh-rahb did you disabled the option to push commits again?

I just would like to push a small fix for the aspect ratio validation.

Sorry, yes I had a secret I needed to push the test. I've removed it and re-enabled now. The test build works!

[meteyou]

@justinh-rahb thx for your contribution!

[justinh-rahb]

Thanks for the quick review and for working through this with me, I really appreciate the consideration and the improvements you made.

There’s a small group of us working on U1 tooling and frontend integration, and while iframe is an imperfect solution today, it’s a meaningful first step toward relying exclusively on mainline Orca without vendor-specific forks or apps.

Thanks again for taking the time 🙏

[justinh-rahb]

I've taken the liberty of preparing a small addition to the docs to address this change: mainsail-crew/gb-docs#23