Drizzle-only database adapter

[joshuasilva414]

We're committing to Drizzle as the only ORM for the initial version. Remove the database adapter interface and use the drizzle db instance directly.

Suggestions

1. Create a light abstraction for building a dialect-agnostic drizzle schema
2. Although there will no longer be an interface to bridge multiple ORMs, there should exist a type representing a drizzle instance of any support dialect (e.g. DrizzleDBInstance) and there will be code to translate some ideas (e.g. timestamps, or "now") into different dialects

Criteria

• Supports major drizzle dialects. At least:
  • sqlite/libsql
  • Postgres
  • MySQL

[linear-code]

HK-253