Decaff driver part 1

[sainthkh]

• Part of Proposal: Convert codebase CoffeeScript => JS => TypeScript #2690
• Prep for Fix Object{N} + options mutation + command display names + big array/object message #5762

NEVER SQUASH THIS PR

[cypress-bot]

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[sainthkh]

A flaky test. All green.

[jennifer-shehane]

nice

[jennifer-shehane]

That was a lot, but I did review it all! Looks good. 👍

[cypress-bot]

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