/**
 * OpenTelemetry instrumentation setup.
 *
 * Opt-in: Only activates when OTEL_ENABLED=true.
 * When disabled, zero overhead (no OTel packages loaded).
 *
 * Loaded by main.ts BEFORE Knex to ensure proper ESM patching.
 *
 * HTTP tracing comes from the `@hono/otel` middleware mounted in
 * `src/http/app.ts` — no Express instrumentation here.
 *
 * Instruments: HTTP (server), Knex (DB), Pino (log correlation), Node.js
 * runtime (event loop, GC, heap). Exports: Prometheus metrics on
 * OTEL_PROMETHEUS_PORT (default 9464). Optional OTLP trace export.
 */
/**
 * No-op: init happens at import time via top-level await.
 * Kept for server.ts lifecycle compatibility.
 */
declare function initTelemetry(): Promise<void>;
/**
 * Gracefully shutdown the OTel SDK, flushing pending telemetry.
 * No-op if OTel was not initialized.
 */
declare function shutdownTelemetry(): Promise<void>;

export { initTelemetry, shutdownTelemetry };