-- Dual-path convergence (Gate B): add columns that Alembic migrations
-- 0120 (is_system) and 0140 (folder_id) add on the core path. Idempotent
-- so both install paths converge to the identical schema.
ALTER TABLE comm_conversations ADD COLUMN IF NOT EXISTS is_system BOOLEAN NOT NULL DEFAULT FALSE;
CREATE INDEX IF NOT EXISTS ix_comm_conversations_tenant_system ON comm_conversations(tenant_id, is_system);
ALTER TABLE comm_conversations ADD COLUMN IF NOT EXISTS folder_id UUID;
CREATE INDEX IF NOT EXISTS ix_comm_conversations_folder ON comm_conversations(folder_id);