[docs]: fix typo in AI Gateway Anthropic model name

[yawbtng]

why

packages/docs/v3/configuration/models.mdx:788 uses gateway/anthropic/claude-sonnet-4.5 with dotted version notation. Every other Anthropic model reference in the docs (and in the rest of this same file) uses Anthropic's canonical hyphenated form (claude-sonnet-4-6, claude-sonnet-4-5-20250929, etc.). A reader who copies this line as-is will hit a model-not-found from the upstream provider.

what changed

One-line fix: claude-sonnet-4.5 → claude-sonnet-4-5-20250929. Picked the dated snapshot used elsewhere for the Sonnet 4.5 family rather than swapping to a different model, to preserve the author's intent.

test plan

• grep across packages/docs/**/*.mdx confirms this was the only dotted-notation Anthropic model name; all other Claude references use hyphenated form.
• No code paths touched.

---

Summary by cubic

Fixed an incorrect Anthropic model name in the gateway docs to use the canonical hyphenated, dated snapshot and avoid model-not-found errors. Updated gateway/anthropic/claude-sonnet-4.5 to gateway/anthropic/claude-sonnet-4-5-20250929.

^{Written for commit ed430f8. Summary will update on new commits.}

[changeset-bot]

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Latest commit: ed430f8

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[github-actions]

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[cubic-dev-ai]

No issues found across 1 file

Confidence score: 5/5

• Automated review surfaced no issues in the provided summaries.
• No files require special attention.

_{Re-trigger cubic}