Clarify the rate-limiting language with additional details

[sabbyanandan]

Ask 1:
The language written as-is is entirely correct. However, we can further expand on what "all Hiro APIs" means. In this case, a single rate-limiting quota is applied to all 3 public-facing APIs: Stacks Blockchain API, Metadata API, and Ordinals API.

For instance, if a developer uses either one or all 3 APIs simultaneously. In that case, the entirety of all API traffic will be attributed to a single default quota, which would be 50 RPM for unauthenticated and 500 RPM for authenticated traffic, respectively.

Let's explicitly state this in the docs so it provides further guidance to developers.

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Ask 2:
In addition to RPM (requests per minute; the primary rate-limiting criteria), we recently introduced secondary rate-limiting criteria in our API infrastructure. Having both kinds is a best practice for any publicly offered API service for added security, better utilization & resource protection, and protecting the API service from abuse.

We want to include a blurb about the secondary rate limit, and in our case, that is 20 RPS (requests per second) for both authenticated and unauthenticated traffic.

[sabbyanandan]

@ryanwaits: I would like to request us to clarify the language soon, so I marked it as "urgent" priority.

cc:/ @CharlieC3 @andresgalante

[ryanwaits]

sorry i let this one slip through the cracks, @sabbyanandan

heres the pr addressing this issue: #594