feat(browser): add `userEvent.wheel` API

[macarie]

Description

Resolves #6936

A couple of notes regarding the API design decision.

Playwright and WebDriverIO both use something like await mouse.wheel(deltaX, deltaY). Their approach isn't tied to any element. Playwright recommends hovering over an element first, then calling this method to trigger a scroll event on it → initial attempt was following that approach with the addition of automatic hover, but this feels very low level.

Another thing worth considering is that one call equals to one event. Usually, testing these interactions require more than that and waiting for a full client-server-client loop, depending on the environment, might be slow.

Landed on something that should provide enough flexibility while keeping a high-level API:

type ScrollOptions = (
  | { direction: 'up' | 'down' | 'left' | 'right' }
  | { delta: { x?: number, y?: number } }
) & { times?: number }

wheel(element: Element, options: ScrollOptions): Promise<void>
wheel(options: ScrollOptions): Promise<void>

[!NOTE] The initially planned element-less version (wheel(options)) was not implemented due to behavior differences between WebDriverIO and Playwright. I'll open a feature request issue to gauge community interest for this addition.

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[macarie]

Looks like there's a huge difference in running times between Firefox and Chrome in WebdriverIO:

 ✓  chrome  wheel.test.ts (9 tests) 11175ms
   ✓ fires wheel event multiple times when `times` option is set  10266ms (repeat x50)
 ✓  firefox  wheel.test.ts (9 tests) 1049ms
   ✓ fires wheel event multiple times when `times` option is set  966ms (repeat x50)

In Playwright all timings are roughly aligned, but all are ~4x slower than Firefox in WebdriverIO:

 ✓  webkit  wheel.test.ts (9 tests) 4422ms
   ✓ fires wheel event multiple times when `times` option is set  4080ms (repeat x50)
 ✓  firefox  wheel.test.ts (9 tests) 4460ms
   ✓ fires wheel event multiple times when `times` option is set  4101ms (repeat x50)
 ✓  chromium  wheel.test.ts (9 tests) 4992ms
   ✓ fires wheel event multiple times when `times` option is set  4591ms (repeat x50)

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[macarie]

Applied the suggestions and split the type (used different interfaces as I was extracting a subtype anyway for the server function)