[Optimizer] Handle API error response when OpModel is turned off

[rpavlovicTT]

Currently, when OpModel (controlled through build flag TTMLIR_ENABLE_OPMODEL) is OFF, all APIs for constraints will return tuple of zeros. Optimizer consumes this response and successfully finishes sharding. Some unit tests pass because of this. However, this is not fully correct behaviour.

With this in mind, we should:

• Change API to throw an error when not implemented
• Handle error response in Optimizer to stop compilation and throw an error
• Sweep through Optimizer mlir unit tests that start breaking after handling API error response as suggested