feat(browser): support clipboard api userEvent.copy, cut, paste

[hi-ogawa]

Description

• closes browser testing: enable (or make it easier) to copy/paste text #6746
• part of Interactivity API for Browser Mode #5770 (comment)

Manually tested on my Linux PC:

• playwright / chromium
• playwright / firefox
• webdriver / chrome
• webdriver / firefox
• preview / chromium

todo

• docs

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[hi-ogawa]

I changed this as it wasn't working when key === 'Ctrl', which is webdriverio's special key to switch modifier keys based on platform. I'm not sure the original code's intent, but it didn't break existing tests.