DB schema finalization and new methods
Created by: rileyp2000
Lines 313-351 are for testing the transaction saving. If you don't want those, comment them out.
This pull request does:
- Separates the db creation strings and constants into another file
- Refines and finalizes the object schemas, including defining types in
types.ts
- Adds several db functions, including get/save cashiers, transactions
- Fixes some other functions so that they work properly