核心 SDK: 跨租户令牌成本冲突、丢弃了 litellm 成功回调以及 NoneType 遮罩导入失败

# telemetry/token_collector.py:69-85
def add_interaction(self, model: str, agent: Optional[str], metrics: TokenMetrics):
    self.total_interactions += 1
    self.total_metrics = self.total_metrics + metrics
    if model not in self.metrics_by_model:
        self.metrics_by_model[model] = TokenMetrics()
    self.metrics_by_model[model] = self.metrics_by_model[model] + metrics
    if agent:
        if agent not in self.metrics_by_agent:
            self.metrics_by_agent[agent] = TokenMetrics()
        self.metrics_by_agent[agent] = self.metrics_by_agent[agent] + metrics  # keyed by bare name