[Feature] Shift test case orchestration to code harness

[Gauravpadam]

The problem

Currently, the backend orchestrates test case execution. Ideally, the backend should only initiate test case execution

Proposed solution

We could introduce driver code for problems which could handle orchestration of testcases and results

Alternatives considered

No. The current model creates a container per test case. Which is okay for self practice but would not work for competitions hosted on LocalCode

Additional context

Also see #2 ; It talks about introducing driver code but for addressing a different problem