feat: migrate transform to 3-layer architecture with per-layer schemas

Remove raw/ layer — staging models now read landing JSON directly.
Rename all model schemas from padelnomics.* to staging.*/foundation.*/serving.*.
Web app queries updated to serving.planner_defaults via SERVING_DUCKDB_PATH.
Supervisor gets daily sleep interval between pipeline runs.

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

transform/sqlmesh_padelnomics/models/foundation/dim_cities.sql

@@ -3,7 +3,7 @@
 -- Cities without Eurostat coverage (US, non-EU) are derived from venue clusters.
 
 MODEL (
-  name padelnomics.dim_cities,
+  name foundation.dim_cities,
   kind FULL,
   cron '@daily',
   grain city_code
@@ -16,7 +16,7 @@ eurostat_cities AS (
     country_code,
     population,
     ref_year
-  FROM padelnomics.stg_population
+  FROM staging.stg_population
   QUALIFY ROW_NUMBER() OVER (PARTITION BY city_code ORDER BY ref_year DESC) = 1
 ),
 -- Venue counts per (country_code, city) from dim_venues
@@ -27,7 +27,7 @@ venue_counts AS (
     COUNT(*)  AS venue_count,
     AVG(lat)  AS centroid_lat,
     AVG(lon)  AS centroid_lon
-  FROM padelnomics.dim_venues
+  FROM foundation.dim_venues
   WHERE city IS NOT NULL AND city != ''
   GROUP BY country_code, city
 ),