feat(portfolio): add stock consolidation domain and schema

app/repositories/postgres.py

@@ -418,6 +418,24 @@ class PostgresPortfolioRepository:
                 ON portfolios (broker, status, updated_at DESC)
                 """
             )
+            cur.execute(
+                """
+                CREATE TABLE IF NOT EXISTS portfolio_corporate_actions (
+                    corporate_action_id UUID PRIMARY KEY,
+                    portfolio_id TEXT NOT NULL,
+                    asset_id UUID NOT NULL,
+                    action_type TEXT NOT NULL CHECK (action_type = 'stock_consolidation'),
+                    effective_date DATE NOT NULL, recorded_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
+                    actor_user_id TEXT, evidence_ref TEXT NOT NULL,
+                    idempotency_key TEXT NOT NULL, payload_hash TEXT NOT NULL,
+                    quantity_before NUMERIC(20,8) NOT NULL, quantity_after NUMERIC(20,8) NOT NULL,
+                    average_price_before NUMERIC(20,8) NOT NULL, average_price_after NUMERIC(20,8) NOT NULL,
+                    total_cost_basis NUMERIC(20,8) NOT NULL, cash_balance NUMERIC(20,8) NOT NULL,
+                    profit_buffer NUMERIC(20,8) NOT NULL, ledger_entry_id BIGINT,
+                    UNIQUE (portfolio_id, idempotency_key)
+                )
+                """
+            )
             cur.execute(
                 """
                 CREATE TABLE IF NOT EXISTS portfolio_comments (