Split up type/schema tests

[ssalbdivad]

As part of the beta release, arktype was split into two packages:

• arktype: The main entry point for type-safe TS syntax
• @arktype/schema: The underlying schema representation and type system

Currently, all the tests are still in arktype and jumbled up between syntax parsing and type system functionality.

The goal of this issue is to split the existing tests into parsing tests that will stay in ark/type/__tests__, and intersection/traversal tests which will move to ark/schema/__tests__ (likely a substantial majority should move).