add new daily sms provider volume report

code generally lifted almost exactly from the daily_volumes_report, but
per provider and only for SMS.

app/dao/fact_billing_dao.py

@@ -779,6 +779,31 @@ def fetch_daily_volumes_for_platform(start_date, end_date):
     return aggregated_totals
 
 
+def fetch_daily_sms_provider_volumes_for_platform(start_date, end_date):
+    # query to return the total notifications sent per day for each channel. NB start and end dates are inclusive
+
+    daily_volume_stats = db.session.query(
+        FactBilling.bst_date,
+        FactBilling.provider,
+        func.sum(FactBilling.notifications_sent).label('sms_totals'),
+        func.sum(FactBilling.billable_units).label('sms_fragment_totals'),
+        func.sum(FactBilling.billable_units * FactBilling.rate_multiplier).label('sms_chargeable_units'),
+        func.sum(FactBilling.billable_units * FactBilling.rate_multiplier * FactBilling.rate).label('sms_cost'),
+    ).filter(
+        FactBilling.notification_type == SMS_TYPE,
+        FactBilling.bst_date >= start_date,
+        FactBilling.bst_date <= end_date,
+    ).group_by(
+        FactBilling.bst_date,
+        FactBilling.provider,
+    ).order_by(
+        FactBilling.bst_date,
+        FactBilling.provider,
+    ).all()
+
+    return daily_volume_stats
+
+
 def fetch_volumes_by_service(start_date, end_date):
     # query to return the volume totals by service aggregated for the date range given
     # start and end dates are inclusive.