[JarvisLabs] Support RTX PRO 6000; update API endpoint; remove spot offers

[peterschmidt85]

• Add JarvisLabs RTX PRO 6000 catalog support.
• Normalize RTX PRO 6000 as RTXPRO6000 and store the original JarvisLabs GPU type in provider_data when needed.
• Use backendn.jarvislabs.net for JarvisLabs offer discovery. JarvisLabs confirmed backendprod.jarvislabs.net and backendn.jarvislabs.net now point to the same region and function identically.
• Do not emit JarvisLabs spot VM offers. JarvisLabs confirmed spot instances are only supported for containers/templates, not VMs.

[jvstme]

(nit) Now that you pass gpu_type in provider_data, it should be possible to normalize GPU names with spaces instead of skipping them (like you suggested in the initial JarvisLabs PR versiom)

[peterschmidt85]

I’d prefer to keep this fail-closed. provider_data["gpu_type"] solves the create-time token issue once we have a reviewed mapping, but it does not make arbitrary spaced GPU names safe to canonicalize. For example, blindly stripping spaces would map RTX A6000 to RTXA6000, while gpuhunt uses A6000.

So I kept unmapped spaced JarvisLabs GPU types skipped with a warning and renamed the warning from “ambiguous” to “unmapped”. For any spaced JarvisLabs token we verify, we can add an explicit mapping.