Fix release compilation

[bgotink]

• Make necessary changes to allow declaration generation to succeed
• Stop emitting declarations in webpack builds, because those land in the sources folders
• Change the build command of pnp to make it work (running build:compile used to delete the output of build:pnp)

[arcanis]

Thanks for this! I took a look myself to see whether it could be fixed without having to add the explicit annotation but that went nowhere. Seems like it's a TS issue 🤷‍♀️

Ignore the version check, I'll be releasing all packages anyway 👍

[bgotink]

Ah I'd already pushed the version check, whoopsie.

Yeah, it seems like enabling declarations makes typescript a bit more strict on these types. I don't fully understand why this error is present though, because typescript could infer the type quite easily to import('clipanion').Usage in this case.

[arcanis]

Manually merged in master, thanks!