feat(sales): add decoupled 17k commercial sales router, ranking engine, and ingestion pipeline

api.py

@@ -10,10 +10,12 @@ import pandas as pd
 from fastapi import FastAPI, Header, HTTPException, Query, Security, status
 from fastapi.middleware.cors import CORSMiddleware
 
+from routes.sales import sales_router
 
 # Production auth secret required for Go backend header integration
 AUTH_SECRET = "hiffi_live_secret_key_prod_2026"
 
+
 def verify_auth_secret(x_auth_secret: Optional[str] = Header(None)) -> str:
     """
     Validates the incoming X-Auth-Secret header for backend-to-backend communication.
@@ -57,6 +59,9 @@ app.add_middleware(
     allow_headers=["*"],
 )
 
+# Mount decoupled commercial sales router
+app.include_router(sales_router)
+
 
 def load_dataset() -> pd.DataFrame:
     """Loads artist dataset with fallback paths."""
@@ -122,6 +127,7 @@ def list_artists(
 ) -> List[Dict[str, Any]]:
     """
     Returns ranked artist list respecting data governance scopes.
+    Strictly locked to the 500-artist telemetry cohort. Zero commercial sales leakage.
     """
     df = load_dataset()
     if df.empty: