feat: Enhance project and scenario creation with monitoring metrics

- Added monitoring metrics for project creation success and error handling in `ProjectRepository`.
- Implemented similar monitoring for scenario creation in `ScenarioRepository`.
- Refactored `run_monte_carlo` function in `simulation.py` to include timing and success/error metrics.
- Introduced new CSS styles for headers, alerts, and navigation buttons in `main.css` and `projects.css`.
- Created a new JavaScript file for navigation logic to handle chevron buttons.
- Updated HTML templates to include new navigation buttons and improved styling for buttons.
- Added tests for reporting service and routes to ensure proper functionality and access control.
- Removed unused imports and optimized existing test files for better clarity and performance.

models/__init__.py

@@ -11,6 +11,7 @@ from .metadata import (
     StochasticVariable,
     StochasticVariableDescriptor,
 )
+from .performance_metric import PerformanceMetric
 from .pricing_settings import (
     PricingImpuritySettings,
     PricingMetalSettings,
@@ -45,4 +46,5 @@ __all__ = [
     "Role",
     "UserRole",
     "password_context",
+    "PerformanceMetric",
 ]