[Optimizer] Optimization pipeline returns success status on failure

[MadhurKumar004]

Location: Optimization/optimizer.py

Description: EdgeFlowOptimizer.apply_pruning returns the original model object if standard dependencies are missing, logging only a warning.

Fix: Raise a OptimizationDependencyError or return a status: failed object so the API can return a 400/500 code or a clear error message.