Decompose hono backend

[rak3rman]

The existing backend codebase was slapped together with a priority on quick development rather than clean development. As of now, the code definitely works but could use some cleanup. Implement the following decomposition tasks:

• [x] Decompose index.ts by applying hono best practices
• [x] Decompose schema.ts into multiple schema files, one per object type
• [x] Add basic testing framework, have home for implementation of #12

Code function shouldn't be modified. We'll focus on polishing the code base in a later issue.