-- Allow pinning a single checklist item to Focus (it stays in its list — the
-- pin just references it, so checking it off in either place is one record).
ALTER TABLE "FocusPin" ADD COLUMN "checklistItemId" TEXT;
CREATE UNIQUE INDEX "FocusPin_checklistItemId_key" ON "FocusPin"("checklistItemId");
ALTER TABLE "FocusPin" ADD CONSTRAINT "FocusPin_checklistItemId_fkey"
    FOREIGN KEY ("checklistItemId") REFERENCES "ChecklistItem"("id") ON DELETE CASCADE ON UPDATE CASCADE;