declare const diag: import("./subsystem.js").SubsystemLogger;
type SessionStateValue = "idle" | "processing" | "waiting";
type SessionRef = {
    sessionId?: string;
    sessionKey?: string;
};
export declare function logWebhookReceived(params: {
    channel: string;
    updateType?: string;
    chatId?: number | string;
}): void;
export declare function logWebhookProcessed(params: {
    channel: string;
    updateType?: string;
    chatId?: number | string;
    durationMs?: number;
}): void;
export declare function logWebhookError(params: {
    channel: string;
    updateType?: string;
    chatId?: number | string;
    error: string;
}): void;
export declare function logMessageQueued(params: {
    sessionId?: string;
    sessionKey?: string;
    channel?: string;
    source: string;
}): void;
export declare function logMessageProcessed(params: {
    channel: string;
    messageId?: number | string;
    chatId?: number | string;
    sessionId?: string;
    sessionKey?: string;
    durationMs?: number;
    outcome: "completed" | "skipped" | "error";
    reason?: string;
    error?: string;
}): void;
export declare function logSessionStateChange(params: SessionRef & {
    state: SessionStateValue;
    reason?: string;
}): void;
export declare function logSessionStuck(params: SessionRef & {
    state: SessionStateValue;
    ageMs: number;
}): void;
export declare function logLaneEnqueue(lane: string, queueSize: number): void;
export declare function logLaneDequeue(lane: string, waitMs: number, queueSize: number): void;
export declare function logRunAttempt(params: SessionRef & {
    runId: string;
    attempt: number;
}): void;
export declare function logActiveRuns(): void;
export declare function startDiagnosticHeartbeat(): void;
export declare function stopDiagnosticHeartbeat(): void;
export { diag as diagnosticLogger };