Why can't my tail worker ever complete its job and why does it get terminated by CF quietly?

export default {
  async tail(events: TailEvent[], env: any, ctx: ExecutionContext): Promise<void> {
    let sequenceNumber = 0;
    const heartbeatInterval = setInterval(() => {
      sequenceNumber++;
      // I do see first five messages in logs (attached)
      console.log(`💓 HEARTBEAT #${sequenceNumber} - Time: ${new Date().toISOString()}`);
    }, 5000);

    const promise = handleTailWorker(events, env, ctx).finally(() => {
      // I do NOT ever see this messgage in the logs
      console.log('🛑 Clearing heartbeat timer');
      clearInterval(heartbeatInterval);
    });

    return await promise;
  }
};

export default {
  async tail(events: TailEvent[], env: any, ctx: ExecutionContext): Promise<void> {
    let sequenceNumber = 0;
    const heartbeatInterval = setInterval(() => {
      sequenceNumber++;
      // I do see first five messages in logs (attached)
      console.log(`💓 HEARTBEAT #${sequenceNumber} - Time: ${new Date().toISOString()}`);
    }, 5000);

    const promise = handleTailWorker(events, env, ctx).finally(() => {
      // I do NOT ever see this messgage in the logs
      console.log('🛑 Clearing heartbeat timer');
      clearInterval(heartbeatInterval);
    });

    return await promise;
  }
};

name = "...-tail"
main = "worker.ts"
compatibility_date = "2024-11-11"
logpush = true

# Routes for tail worker (optional, for health checks)
routes = [
  { pattern = "api....-tail", zone_name = "..." },
]

[observability.logs]
enabled = true

[limits]
cpu_ms = 300_000

name = "...-tail"
main = "worker.ts"
compatibility_date = "2024-11-11"
logpush = true

# Routes for tail worker (optional, for health checks)
routes = [
  { pattern = "api....-tail", zone_name = "..." },
]

[observability.logs]
enabled = true

[limits]
cpu_ms = 300_000