feat: add organization-related models and update schemas for organization management

backend/alembic/versions/6e1c9b2f7a4d_add_active_organization_id.py

@@ -0,0 +1,70 @@
+"""add active organization to users
+
+Revision ID: 6e1c9b2f7a4d
+Revises: 050c16fde00e
+Create Date: 2026-02-08
+"""
+
+from __future__ import annotations
+
+from alembic import op
+import sqlalchemy as sa
+
+# revision identifiers, used by Alembic.
+revision = "6e1c9b2f7a4d"
+down_revision = "050c16fde00e"
+branch_labels = None
+depends_on = None
+
+
+def upgrade() -> None:
+    op.add_column(
+        "users",
+        sa.Column("active_organization_id", sa.UUID(), nullable=True),
+    )
+    op.create_index(
+        "ix_users_active_organization_id",
+        "users",
+        ["active_organization_id"],
+    )
+    op.create_foreign_key(
+        "fk_users_active_organization",
+        "users",
+        "organizations",
+        ["active_organization_id"],
+        ["id"],
+    )
+
+    bind = op.get_bind()
+    rows = bind.execute(
+        sa.text(
+            """
+            SELECT user_id, organization_id
+            FROM organization_members
+            ORDER BY user_id, created_at ASC
+            """
+        )
+    ).fetchall()
+    seen: set[str] = set()
+    for row in rows:
+        user_id = str(row.user_id)
+        if user_id in seen:
+            continue
+        seen.add(user_id)
+        bind.execute(
+            sa.text(
+                """
+                UPDATE users
+                SET active_organization_id = :org_id
+                WHERE id = :user_id
+                  AND active_organization_id IS NULL
+                """
+            ),
+            {"org_id": row.organization_id, "user_id": row.user_id},
+        )
+
+
+def downgrade() -> None:
+    op.drop_constraint("fk_users_active_organization", "users", type_="foreignkey")
+    op.drop_index("ix_users_active_organization_id", table_name="users")
+    op.drop_column("users", "active_organization_id")