Refactor function from module in the backend to catch errors and raise custom exceptions

[MaxenceGui]

Issue Description

At present, several backend functions are not optimally handling exceptions. Some of them return False when they catch an exception, while others use the generic type Exception to catch all possible errors, which is not a good practice as it can hide critical errors that the team needs to address. Additionally, some custom exceptions are being attempted to be caught but are never raised in the first place.

Concerned module:

• azure_storage
• model_inference
  • inference.py
  • model_module.py
• model_request
• app.py

Excluding pipelines_version_insertion.py as another issue is specific to this case

Work to do

Refactor the backend to handle exceptions as per Python standards and provide meaningful error messages.

Acceptance Criteria

• No more generic exceptions are caught or raised unless it is required (avoid server crash for example)
• When errors are caught in a module, the custom exception is raised with the from keyword when necessary

Tasks

• [ ] Modify the azure_storage module to eliminate every return False from catching exception; raise a custom exception instead
• [x] Modify the model_inference module to catch specific exceptions and return the ProcessInferenceResultError custom error
• [ ] Raise a custom exception in model_request if the deployment platform of a model is not supported
• [x] Modify app.py to handle exceptions raised by the module it is using