Fix playground samples type errors and add CI test

[tamayika]

I found several playground samples have type errors.
So I added type checking test script and test CI to github actions.

[hediet]

Looks good, thanks a lot! Please see my comments.

[tamayika]

I made all in parallel.
But it saved only 10sec because Github Action's cpu spec is poor(2cpu).
In my environment(24cpu), it takes only 10sec to process all.

To pass all files to one tsc process failed due to const editor confliction.

[hediet]

Thanks! :)
Generally, please try to not force push to a PR that has been reviewed, as it resets what has been reviewed already. We have the policy to check every changed line we merge to main and a force push forces us to check all the files again.