Undocument x-wait-for-model and x-use-cache headers

[Wauplin]

This PR:

• removes x-wait-for-model and x-use-cache from the headers table. Only the authorization header is kept
• removes some wording around the headers table
• updates the settings page link to the correct finegrained settings https://huggingface.co/settings/tokens/new?ownUserPermissions=inference.serverless.write&tokenType=fineGrained
• moves the headers table above the paramters table

[HuggingFaceDocBuilderDev]

The docs for this PR live here. All of your documentation changes will be reflected on that endpoint. The docs are available until 30 days after the last update.

[pcuenca]

x-use-cache referenced in this blog post (which has now become deprecated, we should redo it).