fix(anthropic): fix sonnet-4.5 thinking

[linkesch]

Follows up on #9065

Fixes #9067 (comment)

Fixes topP is not supported when thinking is enabled.

const agentModel = new ChatAnthropic({
  modelName: "claude-sonnet-4-5",
  maxTokens: 32_000,
  thinking: { type: "enabled", budget_tokens: 1024 },
});

--
x.com/linkesch

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Latest commit: 13161f3

The changes in this PR will be included in the next version bump.

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Name	Type
@langchain/anthropic	Patch

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[hntrl]

Thanks for the fix!