bedrock: Fix Claude Sonnet 5 and Fable 5 routing outside US regions

[aviddiviner]

Follow-up to #60360 and #59016 (cc @NeelChotai @bennetbo).

Claude Sonnet 5 and Claude Fable 5 cannot be invoked with on-demand throughput — AWS requires an inference profile, and only us.* and global.* profiles exist for these models (Sonnet 5 model card, Fable 5 model card).

For users in EU/APAC regions without allow_global enabled, Zed generated profile IDs like eu.anthropic.claude-sonnet-5, which fail with:

ResourceNotFoundException: Model not found.

And falling back to the bare model ID isn't an option either, since direct invocation fails with:

Invocation of model ID anthropic.claude-fable-5 with on-demand throughput isn't supported.
Retry your request with the ID or ARN of an inference profile that contains this model.

Confirmed against the live AWS API — only us.* and global.* profiles exist:

❯ aws bedrock list-inference-profiles --region eu-west-1 \
    --query "inferenceProfileSummaries[?contains(inferenceProfileId, 'sonnet-5') || contains(inferenceProfileId, 'fable')].[inferenceProfileId,status]" \
    --output table
------------------------------------------------
|             ListInferenceProfiles            |
+------------------------------------+---------+
|  global.anthropic.claude-sonnet-5  |  ACTIVE |
|  global.anthropic.claude-fable-5   |  ACTIVE |
+------------------------------------+---------+

This change removes both models from the EU match arm and routes them through the global inference profile when no regional profile is available. US regions continue to use the us.* profile. Verified working from eu-west-1.

Note: this means requests from non-US regions route through the global profile, which may dispatch inference to any supported AWS region. That's inherent to how AWS exposes these models — there is no EU-resident option today.

Release Notes:

• Fixed Claude Sonnet 5 and Claude Fable 5 failing on Amazon Bedrock in non-US regions.

[NeelChotai]

nice! Thank you for the contribution