feat: export types from toplevel

[forivall]

While #411 is marked as closed, it's still bad practice to perform deep imports, and so I'm opening this PR to export the types at the top level.

• [x] Make sure to open an issue as a bug/issue before writing your code! That way we can discuss the change, evaluate designs, and agree on the general idea
• [x] Ensure the tests and linter pass
• [x] Code coverage does not decrease (if any source code was changed) N/A
• [x] ~~Appropriate docs were updated (if necessary)~~ N/A

Fixes #411 🦕

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