feat: Phase 1 Group 8 — add account_id to target_lists (keep team_id)

Zero rows in production — this is a schema-only migration in practice.
team_id kept for app code compatibility. Drop deferred to later cleanup.
Backfill: team_id → team admin user → account_id; fallback: created_by.

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

backend/alembic/versions/2c6aabd89bc6_add_account_id_target_lists.py

@@ -0,0 +1,62 @@
+"""add account_id to target_lists (keep team_id)
+
+Revision ID: 2c6aabd89bc6
+Revises: 78fc200abac1
+Create Date: 2026-04-09 00:00:00.000000
+"""
+from typing import Sequence, Union
+from alembic import op
+import sqlalchemy as sa
+
+revision: str = '2c6aabd89bc6'
+down_revision: Union[str, None] = '78fc200abac1'
+branch_labels: Union[str, Sequence[str], None] = None
+depends_on: Union[str, Sequence[str], None] = None
+
+
+def upgrade() -> None:
+    op.add_column('target_lists', sa.Column('account_id', sa.UUID(), nullable=True))
+    op.create_foreign_key(
+        'fk_target_lists_account_id', 'target_lists', 'accounts',
+        ['account_id'], ['id'], ondelete='CASCADE',
+    )
+
+    # Primary: team_id → team admin user → account_id
+    op.execute("""
+        UPDATE target_lists tl
+        SET account_id = u.account_id
+        FROM users u
+        WHERE u.team_id = tl.team_id
+          AND u.is_team_admin = TRUE
+          AND u.account_id IS NOT NULL
+          AND tl.account_id IS NULL
+    """)
+
+    # Fallback: created_by → users.account_id
+    op.execute("""
+        UPDATE target_lists tl
+        SET account_id = u.account_id
+        FROM users u
+        WHERE tl.created_by = u.id
+          AND u.account_id IS NOT NULL
+          AND tl.account_id IS NULL
+    """)
+
+    result = op.get_bind().execute(
+        sa.text("SELECT COUNT(*) FROM target_lists WHERE account_id IS NULL")
+    )
+    count = result.scalar()
+    if count > 0:
+        raise RuntimeError(
+            f"ROLLBACK: {count} target_lists rows have NULL account_id. "
+            "No team admin found for these teams. Resolve before re-running."
+        )
+
+    op.alter_column('target_lists', 'account_id', nullable=False)
+    op.create_index('ix_target_lists_account_id', 'target_lists', ['account_id'])
+
+
+def downgrade() -> None:
+    op.drop_index('ix_target_lists_account_id', table_name='target_lists')
+    op.drop_constraint('fk_target_lists_account_id', 'target_lists', type_='foreignkey')
+    op.drop_column('target_lists', 'account_id')

backend/app/models/target_list.py

@@ -9,6 +9,7 @@ from app.core.database import Base
 if TYPE_CHECKING:
     from app.models.user import User
     from app.models.team import Team
+    from app.models.account import Account
 
 
 class TargetList(Base):
@@ -21,6 +22,12 @@ class TargetList(Base):
         UUID(as_uuid=True), ForeignKey("teams.id", ondelete="CASCADE"),
         nullable=False, index=True
     )
+    account_id: Mapped[uuid.UUID] = mapped_column(
+        UUID(as_uuid=True),
+        ForeignKey("accounts.id", ondelete="CASCADE"),
+        nullable=False,
+        index=True,
+    )
     created_by: Mapped[Optional[uuid.UUID]] = mapped_column(
         UUID(as_uuid=True), ForeignKey("users.id", ondelete="SET NULL"), nullable=True
     )

backend/tests/test_phase1_migrations.py

@@ -443,3 +443,38 @@ async def test_script_builder_session_account_id(test_db: AsyncSession):
     )
     row = result.scalar_one()
     assert row.account_id == account.id
+
+
+# ── Group 8: TargetList ────────────────────────────────────────────────────────
+
+@pytest.mark.asyncio
+async def test_target_list_account_id_from_team_admin(test_db: AsyncSession):
+    """target_lists.account_id must be set to the team admin's account_id."""
+    from app.models.target_list import TargetList
+    from app.models.team import Team
+
+    account, user = await _make_account_and_user(test_db, "tl1")
+    # Make user a team admin
+    team = Team(name=f"Team {uuid.uuid4().hex[:6]}")
+    test_db.add(team)
+    await test_db.flush()
+
+    user.team_id = team.id
+    user.is_team_admin = True
+    await test_db.flush()
+
+    target_list = TargetList(
+        team_id=team.id,
+        account_id=account.id,
+        created_by=user.id,
+        name="Server Targets",
+        targets=[{"label": "SRV-01"}],
+    )
+    test_db.add(target_list)
+    await test_db.commit()
+
+    result = await test_db.execute(
+        select(TargetList).where(TargetList.id == target_list.id)
+    )
+    row = result.scalar_one()
+    assert row.account_id == account.id