Migrate SQLX to local/dev only

[christoff-linde]

Description

Currently, sqlx and timescaledb is used for the db backend for the project. However, due to complexities with hosting a timescaledb instance, the time has probably come to migrate to using Amazon Timestream. This would remove the need to sqlx in production.

Thus, sqlx and the timescaledb docker setup can probably be migrated to only be used locally, which means that the dependencies can be moved to dev dependencies.

This will require some investigation into how to prevent schema drift (local timescaledb vs timestream) and any other considerations. Additionally, considerations around user auth, sensor config storage, etc., should be considered.

One possible solution could be to:

• Keep the postgres instance, but remove the need for timescaledb extension. The postgres instance can then still be used for user/sensor data storage
• Completely remove the postgres instance, and use AWS-native solutions for sensor config storage, user auth, etc.

Task List

• Move relevant dependencies to be strictly dev dependencies
• Investigate migration requirements