[#58] Updates for jakarta and GHC-9

NB: IsNotInView kinda leaks into user code, and there's not much we can do about it (save for just putting it on IndigoM and then giving it anywhere GHC complains, but even then it's not a silver bullet). IIRC indigo doesn't know about on-chain views, so this is unfortunate. I've added a paragraph to the tutorial to explain why this happens.

Description

Problem: new releases for morley &c were published recently, including an upgrade to GHC-9 and jakarta support.

Solution: bump resolver and dependencies, update the code; one issue is summoner wasn't updated for ghc-9 yet -- reimplement the parts we use by hand, use tree-view to draw pretty unicode-art trees.

Also bumps version.

Related issue(s)

Resolves #58 (closed)

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