feat(client): migration old package to rspack (#15068)

#### PR Dependency Tree


* **PR #15068** 👈

This tree was auto-generated by
[Charcoal](https://github.com/danerwilliams/charcoal)

<!-- This is an auto-generated comment: release notes by coderabbit.ai
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## Summary by CodeRabbit

* **Chores**
* Upgraded Vitest across packages to 4.1.8 and bumped Tailwind PostCSS
to 4.3.0
* CLI/tooling updated to support the media-capture-playground package
and adjust build/dev server behavior

* **Bug Fixes**
  * Improved workspace deletion reliability in the Electron app

* **Refactor**
* Simplified media capture playground build setup (build/config
adjustments)

* **Tests**
* Made tests more robust by preserving/restoring environment state
during runs
<!-- end of auto-generated comment: release notes by coderabbit.ai -->