How to stream and control scrcpy with web browser

- [ ] I have checked that a similar [feature request](https://github.com/Genymobile/scrcpy/issues?q=is%3Aopen+is%3Aissue+label%3A%22feature+request%22) does not already exist.

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The issue names no source files, tests, or entry points and contains only the feature-request template. Start by defining the browser streaming and device-control requirements, then locate the relevant scrcpy architecture; done requires an agreed scope and a validated browser-based solution.

Written by the indexing model from the issue text.