[fix] get packaging test working on Windows

[mrkishi]

Packaging's "watches for changes" test hasn't worked on Windows. Upon investigation it was because of two reasons:

• We need to wait for chokidar's ready event before writing the files;
• Typescript uses crlf on the generated .d.ts files by default, causing a mismatch with our expected output.

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Latest commit: 01cc321

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[Rich-Harris]

Niiiiice