AI Gateway - AI Gateway log IDs and request IDs now use UUIDv7

<p>New AI Gateway <a href="https://developers.cloudflare.com/ai-gateway/observability/logging/">log</a> IDs and request IDs are lowercase UUIDv7, such as <code>019a7b3e-5f2c-7c41-9d3e-2b8f6a1c4e07</code>. Previously, log IDs were 26-character ULIDs and request IDs were random UUIDs.</p> <p>For a request that AI Gateway answers in a single step, the <code>cf-aig-request-id</code>, <code>cf-aig-log-id</code>, and <code>cf-aig-event-id</code> response headers now carry the same value. For provider and Universal requests, if you set your own <code>cf-aig-event-id</code>, AI Gateway returns it instead.</p> <p>Existing log IDs do not change, and the <a href="https://developers.cloudflare.com/api/resources/ai_gateway/subresources/logs/methods/list/">logs API</a> accepts both formats. Treat log IDs as opaque strings, and update any code that checks for the ULID format.</p>