M11: implement operational booking lifecycle

backend/app/api/routers/customers.py

@@ -0,0 +1,41 @@
+from fastapi import APIRouter, Depends, Query
+from sqlalchemy import or_, select
+from sqlalchemy.orm import Session
+
+from app.api.deps import get_current_user, get_db
+from app.models.customer import Customer
+from app.schemas import CurrentUser, CustomerOptionOut
+
+router = APIRouter(prefix="/api/v1/customers", tags=["customers"])
+
+
+@router.get("", response_model=list[CustomerOptionOut])
+def search_customers(
+    query: str = Query(min_length=2, max_length=100),
+    limit: int = Query(default=20, ge=1, le=50),
+    db: Session = Depends(get_db),
+    _user: CurrentUser = Depends(get_current_user),
+) -> list[CustomerOptionOut]:
+    term = f"%{query.strip()}%"
+    customers = db.scalars(
+        select(Customer)
+        .where(
+            Customer.merged_into_customer_id.is_(None),
+            or_(
+                Customer.public_ref.ilike(term),
+                Customer.first_name.ilike(term),
+                Customer.last_name.ilike(term),
+                Customer.email.ilike(term),
+            ),
+        )
+        .order_by(Customer.last_name, Customer.first_name)
+        .limit(limit)
+    ).all()
+    return [
+        CustomerOptionOut(
+            public_ref=customer.public_ref,
+            display_name=f"{customer.first_name} {customer.last_name}",
+            email=customer.email,
+        )
+        for customer in customers
+    ]