[Lake][Stats][App] Test app endpoint and document README.md for how to deploy/test it

[idiom-bytes]

Background / motivation

As a result of deploying duckdb, the accuracy/app has been updated to query from the lake.

This means that at some point, we'll have to redeploy the app and we need to:

TODOs / DoD

1. make sure the app endpoint is working as expected
2. the app needs to have a lake, that it's constantly updating the tables + etl
3. have instructions for how to deploy this
4. have instructions for how to test that it's working
5. make sure the predictoor.ai FE still works once the new server is deployed

Tasks:

• make sure the app endpoint is working as expected
• the app needs to have a lake, that it's constantly updating the tables + etl
• have instructions for how to deploy this
• have instructions for how to test that it's working
• make sure the predictoor.ai FE still works once the new server is deployed

[kdetry]

We do not need ETL, only raw tables are enough for the accuracy module

[idiom-bytes]

Tracking outstanding items (including this) in #1299 and closing this to cleanup the backlog, until we have it resolved.