feat: add sync tracking columns to step_library

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/alembic/versions/fb1481317ff6_add_step_library_sync_fields.py

@@ -0,0 +1,47 @@
+"""add_step_library_sync_fields
+
+Revision ID: fb1481317ff6
+Revises: a1b2c3d4e5f6
+Create Date: 2026-02-25 03:19:52.600292
+
+"""
+from typing import Sequence, Union
+
+from alembic import op
+import sqlalchemy as sa
+
+
+# revision identifiers, used by Alembic.
+revision: str = 'fb1481317ff6'
+down_revision: Union[str, None] = 'a1b2c3d4e5f6'
+branch_labels: Union[str, Sequence[str], None] = None
+depends_on: Union[str, Sequence[str], None] = None
+
+
+def upgrade() -> None:
+    op.add_column('step_library', sa.Column('source_tree_id', sa.UUID(), nullable=True))
+    op.add_column('step_library', sa.Column('source_node_id', sa.String(255), nullable=True))
+    op.add_column('step_library', sa.Column('is_flow_synced', sa.Boolean(), nullable=False, server_default='false'))
+    op.add_column('step_library', sa.Column('last_synced_at', sa.DateTime(timezone=True), nullable=True))
+    op.create_foreign_key(
+        'fk_step_library_source_tree',
+        'step_library', 'trees',
+        ['source_tree_id'], ['id'],
+        ondelete='SET NULL'
+    )
+    op.create_unique_constraint(
+        'uq_step_library_source_node',
+        'step_library',
+        ['source_tree_id', 'source_node_id']
+    )
+    op.create_index('ix_step_library_source_tree_id', 'step_library', ['source_tree_id'])
+
+
+def downgrade() -> None:
+    op.drop_index('ix_step_library_source_tree_id', 'step_library')
+    op.drop_constraint('uq_step_library_source_node', 'step_library', type_='unique')
+    op.drop_constraint('fk_step_library_source_tree', 'step_library', type_='foreignkey')
+    op.drop_column('step_library', 'last_synced_at')
+    op.drop_column('step_library', 'is_flow_synced')
+    op.drop_column('step_library', 'source_node_id')
+    op.drop_column('step_library', 'source_tree_id')