chore: Sync demos from internal package

[avinashbot]

Issue #, if available: n/a

Description of changes: Too lazy to go fetch all the changes required. There are still some manual fixes I had to make, mostly around @typescript-eslint/no-unused-vars, since the removed code blocks left orphan variables and imports. Not sure how to fix it, not in the mood to dig around codemods today, plus we're a little behind on changes.

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