fix: Correct migration down_revision to main branch

Change down_revision from 'add_modelled_policies' (only exists on
feat/modelled-policies branch) to '886921687770' (last migration on main).

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

Author: SakshiKekre

alembic/versions/20260310_67608331ee8a_add_parameter_nodes_table.py

@@ -15,7 +15,7 @@
 
 # revision identifiers, used by Alembic.
 revision: str = "67608331ee8a"
-down_revision: Union[str, Sequence[str], None] = "add_modelled_policies"
+down_revision: Union[str, Sequence[str], None] = "886921687770"
 branch_labels: Union[str, Sequence[str], None] = None
 depends_on: Union[str, Sequence[str], None] = None