POST /api route for creating new brew does not validate inputs

[AlexeySachkov]

This is not an important issue, but I think it would be good to design this API in better way to validate all possible inputs and return meaningful errors if something is wrong.

At the moment, I've found the following:

We do not validate fields description, tags, systems, published, createdAt, updatedAt, lastViewed, views, version and it is possible to insert some custom info there through API.

We return 500 Internal Server Error if some mandatory fields like text are missing.