Update limits.mdx

added new limit of 500 logs that can be stored per second per gateway

Author: kathayl

src/content/docs/ai-gateway/reference/limits.mdx

@@ -16,6 +16,7 @@ The following limits apply to gateway configurations, logs, and related features
 | Datasets                                                        | 10 per gateway                      |
 | Gateways                                                        | 10 per account                      |
 | Gateway name length                                             | 64 characters                       |
+| Log storage rate limit                                          | 500 logs per second per gateway     |
 | Logs stored [paid plan](/ai-gateway/reference/pricing/)         | 10 million per gateway <sup>1</sup> |
 | Logs stored [free plan](/ai-gateway/reference/pricing/)         | 100,000 per account <sup>2</sup>    |
 | Log size stored                                                 | 10 MB per log <sup>3</sup>          |