feat: add admin settings system and improve customer/pricing endpoints

Add centralized admin settings (company info, social links, quick calls,
sidebar visibility toggles, theme, logo upload) with singleton pattern
and full CRUD API. Add active/dedicated customer count endpoints for
dashboard stats. Fix automatic assignment route to use PUT instead of
GET. Refactor oil price endpoint to use schema serialization with null
safety.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

app/customer/views.py

@@ -8,7 +8,8 @@ from app.common.decorators import login_required as common_login_required
 from app.common.responses import error_response, success_response
 
 logger = logging.getLogger(__name__)
-from datetime import datetime
+from datetime import datetime, timedelta
+from sqlalchemy import func
 from app.classes.cards import Card_Card
 from app.classes.customer import \
     Customer_Customer, \
@@ -18,6 +19,7 @@ from app.classes.customer import \
     Customer_Tank_Inspection_schema,\
     Customer_Tank_Inspection
 from app.classes.service import Service_Parts
+from app.classes.delivery import Delivery_Delivery
 from app.classes.admin import Admin_Company
 from app.classes.auto import Auto_Delivery,Auto_Delivery_schema
 from app.classes.stats_customer import Stats_Customer
@@ -437,6 +439,38 @@ def customer_count():
     return success_response({'count': get_customer})
 
 
+@customer.route("/count/active", methods=["GET"])
+@login_required
+def customer_count_active():
+    """
+    Count distinct customers who had a delivery within the past year.
+    """
+    logger.info("GET /customer/count/active - Getting active past year count")
+    one_year_ago = datetime.utcnow().date() - timedelta(days=365)
+    count = (db.session
+             .query(func.count(func.distinct(Delivery_Delivery.customer_id)))
+             .filter(Delivery_Delivery.when_delivered >= one_year_ago)
+             .scalar())
+    return success_response({'count': count or 0})
+
+
+@customer.route("/count/dedicated", methods=["GET"])
+@login_required
+def customer_count_dedicated():
+    """
+    Count distinct customers with more than one finalized delivery.
+    """
+    logger.info("GET /customer/count/dedicated - Getting dedicated customer count")
+    subquery = (db.session
+                .query(Delivery_Delivery.customer_id)
+                .filter(Delivery_Delivery.delivery_status == 10)
+                .group_by(Delivery_Delivery.customer_id)
+                .having(func.count(Delivery_Delivery.id) > 1)
+                .subquery())
+    count = db.session.query(func.count()).select_from(subquery).scalar()
+    return success_response({'count': count or 0})
+
+
 @customer.route("/automatic/status/<int:customer_id>", methods=["GET"])
 @login_required
 def customer_automatic_status(customer_id):
@@ -475,7 +509,7 @@ def get_all_automatic_deliveries():
 
 
 
-@customer.route("/automatic/assign/<int:customer_id>", methods=["GET"])
+@customer.route("/automatic/assign/<int:customer_id>", methods=["PUT"])
 @login_required
 def customer_automatic_assignment(customer_id):
     """