Interview classics: Promise.all and debounce

Write the two most-asked async functions from Topic 15.7, without using Promise.all, allSettled, race or any inside them.

1. promiseAll(iterable) returns a promise of all results in input order. It accepts any iterable (arrays, Sets) and plain values, resolves [] for empty input, and rejects with the first rejection.

2. debounce(fn, ms) returns a function that runs fn only after calls have stopped for ms milliseconds, with the latest arguments and the caller's this.

Then make the search box show Searching for: <text> in #out 200 ms after the user stops typing.

What Check tests

promiseAll keeps input order and accepts plain values
promiseAll([]) resolves to an empty array
promiseAll rejects with the first error
promiseAll accepts any iterable, such as a Set
debounce runs once, with the latest arguments, after calls stop
debounce keeps this
The search box updates 200 ms after typing stops

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Interview classics: Promise.all and debounce