feat: Crossmint type + useCrossmint

[mPaella]

Description

as discussed:

• changing Crossmint from a class to a type
• creating useCrossmint and CrossmintProvider
• i added a little utility function createCrossmint, which just validates the api key as well

Test plan

not much to test, just a simple type and hook

[changeset-bot[bot]]

⚠️ No Changeset found

Latest commit: 4082f1cee7cc0fb06c5b1ac21b632b93d6e50757

Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go. If these changes should result in a version bump, you need to add a changeset.

This PR includes no changesets

When changesets are added to this PR, you'll see the packages that this PR includes changesets for and the associated semver types

Click here to learn what changesets are, and how to add one.

Click here if you're a maintainer who wants to add a changeset to this PR

[devlyn37]

Closing as I think another PR with similar changes has landed