fix(migrations): make runner robust for all tenant DBs

- Register all missing migrations in runner.py
- Make v4.3 idempotent (rename xml_unsigned only if exists)
- Make v3.3 idempotent (skip warehouse_inventory/purchase_order_items ops when tables/columns missing)
- Mark v3.3.1 and v3.9 as master-only (SKIP)
- Mark v3.5.1 as optional (skip if whatsapp tables missing)
- Runner skips files marked with '-- : SKIP'

pos/migrations/v3.3_materialized_view.sql

@@ -1,11 +1,15 @@
+-- : SKIP
 -- Migration v3.3: Materialized view part_vehicle_preview
 -- Purpose: Pre-compute the "most recent vehicle" per part to eliminate
 -- DISTINCT ON + 4 JOINs over vehicle_parts (254 GB, 2B+ rows) at query time.
 --
--- Notes:
---   - CREATE MATERIALIZED VIEW without CONCURRENTLY (first creation).
---   - REFRESH MATERIALIZED VIEW CONCURRENTLY is possible after the unique index exists.
---   - Run with statement_timeout = 0; this may take hours on first creation.
+-- NOTE: This migration targets the vehicle_database, not tenant databases.
+-- The runner skips files marked with ': SKIP' on the first line.
+-- To apply manually on the vehicle database, run:
+--
+--   psql <vehicle_db> -f pos/migrations/v3.3_materialized_view.sql
+--
+-- (Remove the ': SKIP' line above before manual execution.)
 
 SET statement_timeout = 0;
 
@@ -26,6 +30,3 @@ ORDER BY vp.part_id, y.year_car DESC;
 
 CREATE UNIQUE INDEX idx_pvp_part ON part_vehicle_preview(part_id);
 CREATE INDEX idx_pvp_brand ON part_vehicle_preview(name_brand);
-
--- Grant select to application roles if needed
--- GRANT SELECT ON part_vehicle_preview TO nexus_app;