Get Analytics Overview

Get overview analytics for an organization.

This endpoint provides summary analytics data for an organization, with optional filtering
by date range, phone number, and assistant.

Parameters:
request (Request): The FastAPI request object
analytics_request (AnalyticsRequest): Analytics request parameters including date range and filters
db (AsyncSession): Database session (injected)
organization_id (Optional[int]): Organization ID from the API key or request

Returns:
Dict[str, Any]: Overview analytics data for the organization

Raises:
HTTPException:
- 400: If organization ID is missing
- 422: If there's a validation error in the request parameters
- 500: If an unexpected error occurs during analytics retrieval