chore: bump github.com/anthropics/anthropic-sdk-go from 1.17.0 to 1.18.0 (#20795)

Bumps
[github.com/anthropics/anthropic-sdk-go](https://github.com/anthropics/anthropic-sdk-go)
from 1.17.0 to 1.18.0.
<details>
<summary>Release notes</summary>
<p><em>Sourced from <a
href="https://github.com/anthropics/anthropic-sdk-go/releases">github.com/anthropics/anthropic-sdk-go's
releases</a>.</em></p>
<blockquote>
<h2>v1.18.0</h2>
<h2>1.18.0 (2025-11-14)</h2>
<p>Full Changelog: <a
href="https://github.com/anthropics/anthropic-sdk-go/compare/v1.17.0...v1.18.0">v1.17.0...v1.18.0</a></p>
<h3>Features</h3>
<ul>
<li><strong>api:</strong> add support for structured outputs beta (<a
href="https://github.com/anthropics/anthropic-sdk-go/commit/fb9cfb4e4b571d5fec7da9874610aa8820aee80c">fb9cfb4</a>)</li>
</ul>
<h3>Chores</h3>
<ul>
<li>bump gjson version (<a
href="https://github.com/anthropics/anthropic-sdk-go/commit/69b5e0e40757884bece66397fb6ca769f4e00118">69b5e0e</a>)</li>
</ul>
</blockquote>
</details>
<details>
<summary>Changelog</summary>
<p><em>Sourced from <a
href="https://github.com/anthropics/anthropic-sdk-go/blob/main/CHANGELOG.md">github.com/anthropics/anthropic-sdk-go's
changelog</a>.</em></p>
<blockquote>
<h2>1.18.0 (2025-11-14)</h2>
<p>Full Changelog: <a
href="https://github.com/anthropics/anthropic-sdk-go/compare/v1.17.0...v1.18.0">v1.17.0...v1.18.0</a></p>
<h3>Features</h3>
<ul>
<li><strong>api:</strong> add support for structured outputs beta (<a
href="https://github.com/anthropics/anthropic-sdk-go/commit/fb9cfb4e4b571d5fec7da9874610aa8820aee80c">fb9cfb4</a>)</li>
</ul>
<h3>Chores</h3>
<ul>
<li>bump gjson version (<a
href="https://github.com/anthropics/anthropic-sdk-go/commit/69b5e0e40757884bece66397fb6ca769f4e00118">69b5e0e</a>)</li>
</ul>
</blockquote>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a
href="https://github.com/anthropics/anthropic-sdk-go/commit/f4266c4d6cb52f0efd239777f322db2387168334"><code>f4266c4</code></a>
release: 1.18.0</li>
<li><a
href="https://github.com/anthropics/anthropic-sdk-go/commit/e3776089b6095d27726c31d82a8e2c9f12bd0cf1"><code>e377608</code></a>
feat(api): add support for structured outputs beta</li>
<li><a
href="https://github.com/anthropics/anthropic-sdk-go/commit/fc01187b262243230c5f5a89c08d835d65b17c6d"><code>fc01187</code></a>
codegen metadata</li>
<li><a
href="https://github.com/anthropics/anthropic-sdk-go/commit/4e9c5a8a928a43e81a133a18ef0396907d833c6a"><code>4e9c5a8</code></a>
codegen metadata</li>
<li>See full diff in <a
href="https://github.com/anthropics/anthropic-sdk-go/compare/v1.17.0...v1.18.0">compare
view</a></li>
</ul>
</details>
<br />


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go.sum

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