Update to Sanity v4, update dependencies, fix TypeScript build error

[kenjonespizza]

• Upgrade to Sanity v4
• Update related Sanity dependencies
• Fix TypeScript error affecting build

Description of changes

Hi! I'm simply looking to get this plugin up to the Sanity v4. It's okay if you don't want to merge this PR, but I figured I'd do my due diligence here 😄

Fixes #72

How to validate the changes

Most of the changes are simply updating to latest version, which I did test the plugin still worked as well as I knew how. Additionally, I had to make a the small changes to src/hooks/usePageTree.ts and src/hooks/usePageTreeItem.ts to get the typescript not to error out. Thanks!

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[richhiggins]

Hey @tstikvoort 👋, we have a few customers needing this upgrade. It would be great if you could get some eyes on @kenjonespizza's PR here 🙏.

[tstikvoort]

@richhiggins thanks for pointing this out! We missed this PR, but very nice it's opened. Thanks for that @kenjonespizza.

I'll try to have a look and test it this week and release it afterwards. Otherwise it'll be next week!

[tstikvoort]

@kenjonespizza once again, thanks for you PR! I noticed that the workflow that installs packages and runs the build, test and linting scripts wasn't working on PRs based on forks. ✅ If you update your fork with the last commit on main it should run (after approval from us).

I expect more is needed to implement a bump to v4 (for example updating package next-sanity) and I was running into issues when installing dependencies locally.

[kenjonespizza]

I expect more is needed to implement a bump to v4 (for example updating package next-sanity) and I was running into issues when installing dependencies locally.

Hi @tstikvoort 👋. I'm unsure exactly how you want handle upgrades here. I took a couple stabs at this that you can checkout or I can PR.

1. This Draft PR Is my attempt to upgrade all dependancies to the latest. I believe everything worked for me but Im less familiar with how this plugin works/builds.
2. This Draft PR Just upgrades Sanity related dependancies (like next-sanity) as well as a few other dependancies that I had to upgrade for the Sanity dependancies to work. I know there are more file changes here, but most are just formatting 🤷‍♂️.

Let me know if you have thoughts here and I can push changes to this PR so it can be tested by you all 😄