/**
 * What a new turn needs to know when the turn before it stopped unfinished.
 * A new turn sees earlier turns as text only, and a turn cut off mid-tool may
 * have no text at all, so without this a "continue" redoes every step. The
 * record comes from the run ledger, which a crash cannot lose the way it can
 * lose the thread's saved reply. Null when the previous turn finished, never
 * started, or ran no tools; a caution, not null, when that cannot be read.
 */
export declare function loadStoppedPreviousTurnNote(threadId: string, turnId: string): Promise<string | null>;