Add tests

[DylanPiercey]

Description

This is a WIP branch to add some tests.

Currently also switches to npm workspaces.

Checklist:

• [ ] I have updated/added documentation affected by my changes.
• [ ] I have added tests to cover my changes.

[changeset-bot[bot]]

🦋 Changeset detected

Latest commit: 5bc187bf3220b3018c2abc7e3a1d07a33384adb6

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

| Name | Type | | ---------------------- | ----- | | @marko/language-server | Patch |

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