/**
 * Chatbot Conversation Store
 *
 * Tracks multi-turn conversation history per phone number for the HTTP chatbot client.
 * Only used in standalone mode (plugin mode uses chatter's own conversation handling).
 *
 * Module-level singleton, single-process only - see docs/ARCHITECTURE.md's
 * "Single-process state caveat". `sweepConversations` gives it the same TTL
 * sweep as `src/core/context.ts` and `src/routes/call/pending.ts`; plugin and
 * standalone mode call it from the shared cleanup tick (see `src/core/mount.ts`)
 * with `contextTtlMs`, so an idle conversation doesn't outlive its context.
 * `conversationId` is minted locally (`crypto.randomUUID()`) purely for
 * log/DB correlation - it is never sent to the remote chatbot API and does
 * not change across calls from the same number, so read
 * `talker_sessions.conversation_id` as "which in-process chatbot
 * conversation produced this row," not as a per-call identifier.
 */
import type { ChatConversation } from "./types";
export declare function getOrCreateConversation(phoneNumber: string, systemMessage?: string): ChatConversation;
export declare function addUserMessage(phoneNumber: string, content: string, systemMessage?: string): void;
export declare function addBotMessage(phoneNumber: string, content: string, systemMessage?: string): void;
export declare function getConversation(phoneNumber: string): ChatConversation | undefined;
export declare function clearConversation(phoneNumber: string): void;
export declare function clearAllConversations(): void;
/**
 * Delete conversations idle for longer than `ttlMs`. Without this a caller
 * who never triggers `clearConversation` - nothing in src/routes/ calls it -
 * would leak an entry for the process lifetime.
 */
export declare function sweepConversations(ttlMs: number): void;