fix: Update notebooks to use public_marts schema

dbt creates mart tables in public_marts schema, not public.
Updated all notebook SQL queries to use the correct schema.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

notebooks/overview/livability_choropleth.ipynb

@@ -49,8 +49,8 @@
     "    amenity_score,\n",
     "    population,\n",
     "    median_household_income\n",
-    "FROM mart_neighbourhood_overview\n",
-    "WHERE year = (SELECT MAX(year) FROM mart_neighbourhood_overview)\n",
+    "FROM public_marts.mart_neighbourhood_overview\n",
+    "WHERE year = (SELECT MAX(year) FROM public_marts.mart_neighbourhood_overview)\n",
     "ORDER BY livability_score DESC\n",
     "\"\"\"\n",
     "\n",