move RequestEvent and ResolveOptions as public types

[elliott-with-the-longest-name-on-github]

#4805 only explicitly requested moving RequestEvent to index.d.ts, but ResolveOptions is also part of Handle's input API, so I moved it too. If, for some reason, we don't want that to be a publicly-accessible type, I'll move it back.

Fixes #4805.

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[ignatiusmb]

Please sort the changes alphabetically

[elliott-with-the-longest-name-on-github]

@ignatiusmb

Sorry about that! Been on vacation. Didn't even think to check for sorting -- I figured that was something the linter handled. Done!

[ignatiusmb]

Thanks!

[Rich-Harris]

thank you!