phase 14-15: docker build validation and helm deployment

infra/migrations/011_paper_trading_positions_unique.sql

@@ -0,0 +1,7 @@
+-- Stonks Oracle - Add unique constraint for paper trading position upserts
+-- Requirements: 8.1, 8.3
+
+-- The paper trading adapter needs to upsert positions by (broker_account_id, ticker).
+-- Add a unique constraint to support ON CONFLICT.
+CREATE UNIQUE INDEX IF NOT EXISTS idx_positions_account_ticker
+    ON positions(broker_account_id, ticker);