Add imports to all reference docs, make more uniform

[edemaine]

As discussed in Discord, this PR adds imports for all the Solid API reference documentation, mostly copying from the old docs, plus a few fixes/additions (in particular trying to ensure that all types are imported too). Also included is some unification:

• getRequestEvent didn't even have a function declaration. Rewrote to include one.
• Use " over ' in imports.
• Don't use ; in imports. (I tried to go with the majority here. I also didn't check all of them, just the ones I was editing. Previously it was pretty inconsistent; if you'd prefer semicolons, I can revert.)

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