fix(migrations): harden BAT-025 PostgreSQL verification

migrations/env.py

@@ -10,13 +10,14 @@ from app.core.config import get_settings
 config = context.config
 
 if config.config_file_name is not None:
-    fileConfig(config.config_file_name)
+    # Alembic may run in-process (bootstrap/tests); preserve application loggers.
+    fileConfig(config.config_file_name, disable_existing_loggers=False)
 
 target_metadata = None
 
 
 def _configure_database_url() -> str:
-    settings = get_settings()
+    settings = config.attributes.get("portfoliohub_settings") or get_settings()
     database_url = settings.active_database_url
     config.set_main_option("sqlalchemy.url", database_url.replace("%", "%%"))
     return database_url

migrations/versions/20260605_0025_ledger_consolidation.py

@@ -18,7 +18,9 @@ depends_on: str | Sequence[str] | None = None
 
 
 def upgrade() -> None:
-    op.add_column("portfolio_ledger", sa.Column("ledger_entry_id", sa.BigInteger(), sa.Identity(always=False), nullable=True))
+    # PostgreSQL identity columns are implicitly NOT NULL.  ``nullable=True``
+    # renders a conflicting trailing ``NULL`` clause on a real PostgreSQL DB.
+    op.add_column("portfolio_ledger", sa.Column("ledger_entry_id", sa.BigInteger(), sa.Identity(always=False), nullable=False))
     op.add_column("portfolio_ledger", sa.Column("order_id", sa.Text(), nullable=True))
     op.add_column("portfolio_ledger", sa.Column("execution_id", sa.Text(), nullable=True))
     op.add_column("portfolio_ledger", sa.Column("side", sa.Text(), nullable=True))