feat: 5-tier pricing, market ticker integration, and delivery stats

Major update spanning pricing, market data, and analytics:

- Pricing: Replace single-price service fees with 5-tier pricing for
  same-day, prime, and emergency deliveries across create/edit/finalize
- Market: Add Ticker_Price and CompanyPrice models with endpoints for
  live commodity prices (HO, CL, RB) and competitor price tracking
- Stats: Add daily/weekly/monthly gallons endpoints with multi-year
  comparison and YoY totals for the stats dashboard
- Delivery: Add map and history endpoints, fix finalize null-driver crash
- Schema: Change fill_location from INTEGER to VARCHAR(250), add
  pre_load normalization for customer updates, fix admin auth check

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

app/customer/views.py

@@ -588,17 +588,14 @@ def edit_customer_tank(customer_id):
     response_last_tank_inspection = data.get("last_tank_inspection", None)
     response_tank_size = data.get("tank_size", 0)
     
-    # --- FIX APPLIED HERE ---
-    # 1. Get the value from the request. Default to 0 if it's missing.
-    response_customer_fill_location = data.get("fill_location", 0)
-    
-    # 2. Add a safety check: if the frontend sent an empty string, convert it to 0.
-    if response_customer_fill_location == "":
-        response_customer_fill_location = 0
+    # Updated to allow string values
+    response_customer_fill_location = data.get("fill_location")
 
     get_customer_tank.last_tank_inspection = response_last_tank_inspection
     get_customer_tank.tank_size = response_tank_size
-    get_customer_description.fill_location = response_customer_fill_location
+    
+    if response_customer_fill_location is not None:
+        get_customer_description.fill_location = response_customer_fill_location
 
     if get_customer.customer_automatic == 1:
         get_auto_info = db.session.query(Auto_Delivery).filter(Auto_Delivery.customer_id == customer_id).first()