feat(genapi): add maximum billing faq (#4566)

* feat(genapi): update generative-apis.mdx

* Apply suggestions from code review

Co-authored-by: Rowena Jones <36301604+RoRoJ@users.noreply.github.com>

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Co-authored-by: Benedikt Rollik <brollik@scaleway.com>
Co-authored-by: Rowena Jones <36301604+RoRoJ@users.noreply.github.com>

Author: 3 people

faq/generative-apis.mdx

@@ -29,6 +29,12 @@ Note that:
 - Cockpits are isolated by Projects, hence you first need to select the right project in the Scaleway console before accessing Cockpit to see your token consumption for this Project (you can see the `project_id` in the Cockpit URL: `https://{project_id}.dashboard.obs.fr-par.scw.cloud/`.
 - Cockpit graphs can take up to 1 hour to update token consumption, see [Troubleshooting](https://www.scaleway.com/en/docs/generative-apis/troubleshooting/fixing-common-issues/#tokens-consumption-is-not-displayed-in-cockpit-metrics) for further details.
 
+## Can I configure a maximum billing threshold?
+Currently, you cannot configure a specific threshold after which your usage will blocked. However:
+- You can [configure billing alerts](/billing/how-to/use-billing-alerts/) to ensure you are warned when you hit specific budget thresholds.
+- Your total billing remains limited by the amount of tokens you can consume within [rate limits](/generative-apis/reference-content/rate-limits/).
+- If you want to ensure fixed billing, you can use [Managed Inference](https://www.scaleway.com/en/inference/), which provides the same set of OpenAI-compatible APIs and a wider range of models.
+
 ## How can I access and use the Generative APIs?
 Access is open to all Scaleway customers. You can start by using the Generative APIs Playground in the Scaleway console to experiment with different models. For integration into applications, you can use the OpenAI-compatible APIs provided by Scaleway. Detailed instructions are available in our [Quickstart guide](/generative-apis/quickstart/).