Align Error Responses Between Python and PostgREST Hivemind Servers

Currently, PostgREST tests follow different error-handling patterns compared to the Python Hivemind server, due to the complexity involved in replicating the same errors. This discrepancy results in different error responses between the two servers.

Since we intend to phase out the Python server, it's crucial to ensure that both servers produce identical error responses to prevent client-side issues during the transition.

Objective:

Identify the differences in error responses between the PostgREST and Python servers.
Determine the feasibility of implementing an error-handling layer in the PostgREST functions to transform errors into the expected format.