Preserve house number from user query when Nominatim omits it

Many addresses resolve to just the road in Nominatim (no house_number
in response). Now extracts the leading number from the user's original
search query and prepends it to the road name, so "123 Adelaide Terrace"
stays as "123 Adelaide Terrace" instead of just "Adelaide Terrace".

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

backend/app/routers/locations.py

@@ -8,6 +8,7 @@ import json
 import urllib.request
 import urllib.parse
 import logging
+import re
 
 from app.database import get_db
 from app.models.location import Location
@@ -70,6 +71,12 @@ async def search_locations(
             addr = item.get("address", {})
             house_number = addr.get("house_number", "")
             road = addr.get("road", "")
+            # If Nominatim didn't return a house_number but the user's
+            # query starts with one, preserve it from the original query.
+            if not house_number and road:
+                m = re.match(r"^(\d+[\w/-]*)\s+", q.strip())
+                if m:
+                    house_number = m.group(1)
             # Build a name that preserves the house number
             if house_number and road:
                 name = f"{house_number} {road}"