Update Bedrock model pricing catalog

[VasiliyRad]

Summary

• add current Bedrock pricing and deployment aliases for GPT-6.1 Sol, GPT-6 Sol, GPT-6 Luna, GPT-6 Astra, Grok 4.6, and Grok 4.7
• add alias-level price-region pinning so regional Mantle IDs and global inference profiles resolve to the correct price rows
• document and test region pinning, launch boundaries, channel isolation, long-context rates, and packaged catalog behavior
• bump metergraph-core to 0.2.51

Verification

• pytest core/tests server/tests -q (638 passed, 12 skipped)
• python3 core/tests/package/verify_artifacts.py (sdist and wheel verified)
• git diff --check

Sources

Pricing and availability are sourced from the corresponding official Amazon Bedrock model cards linked from each catalog row.