chore(deps): Bump diff from 8.0.4 to 9.0.0 (#1187)

Bumps [diff](https://github.com/kpdecker/jsdiff) from 8.0.4 to 9.0.0.
<details>
<summary>Changelog</summary>
<p><em>Sourced from <a
href="https://github.com/kpdecker/jsdiff/blob/master/release-notes.md">diff's
changelog</a>.</em></p>
<blockquote>
<h2>9.0.0</h2>
<p>(All changes part of PR <a
href="https://redirect.github.com/kpdecker/jsdiff/pull/672">#672</a>.)</p>
<ul>
<li>
<p><strong>ES5 support is dropped</strong>. <code>parsePatch</code> now
uses <code>TextDecoder</code> and <code>Uint8Array</code>, which are not
available in ES5, and TypeScript is now compiled with the
&quot;es6&quot; <code>target</code>. From now on, I intend to freely use
any features that are deemed &quot;Widely available&quot; by <a
href="https://web.dev/baseline">Baseline</a>. Users who need ES5 support
should stick to version 8.</p>
</li>
<li>
<p><strong>C-style quoted strings in filename headers are now properly
supported</strong>.</p>
<p>When the name of either the old or new file in a patch contains
&quot;special characters&quot;, both GNU <code>diff</code> and Git quote
the filename in the patch's headers and escape special characters using
the same escape sequences that are used in string literals in C,
including octal escapes for all non-ASCII characters. Previously, jsdiff
had very little support for this; <code>parsePatch</code> would remove
the quotes, and unescape any escaped backslashes, but would not unescape
other escape sequences. <code>formatPatch</code>, meanwhile, did not
quote or escape special characters at all.</p>
<p>Now, <code>parsePatch</code> parses all the possible escape sequences
that GNU diff (or Git) ever output, and <code>formatPatch</code> quotes
and escapes filenames containing special characters in the same way GNU
diff does.</p>
</li>
<li>
<p><strong><code>formatPatch</code> now omits file headers when
<code>oldFileName</code> or <code>newFileName</code> in the provided
patch object are <code>undefined</code></strong>, regardless of the
<code>headerOptions</code> parameter. (Previously, it would treat the
absence of <code>oldFileName</code> or <code>newFileName</code> as
indicating the filename was the word &quot;undefined&quot; and emit
headers <code>--- undefined</code> / <code>+++ undefined</code>.)</p>
</li>
<li>
<p><strong><code>formatPatch</code> no longer outputs trailing tab
characters at the end of <code>---</code>/<code>+++</code>
headers.</strong></p>
<p>Previously, if <code>formatPatch</code> was passed a patch object to
serialize that had empty strings for the <code>oldHeader</code> or
<code>newHeader</code> property, it would include a trailing tab
character after the filename in the <code>---</code> and/or
<code>+++</code> file header. Now, this scenario is treated the same as
when <code>oldHeader</code>/<code>newHeader</code> is
<code>undefined</code> - i.e. the trailing tab is omitted.</p>
</li>
<li>
<p><strong><code>formatPatch</code> no longer mutates its input</strong>
when serializing a patch containing a hunk where either the old or new
content contained zero lines. (Such a hunk occurs only when the hunk has
no context lines and represents a pure insertion or pure deletion, which
for instance will occur whenever one of the two files being diffed is
completely empty.) Previously <code>formatPatch</code> would provide the
correct output but also mutate the <code>oldLines</code> or
<code>newLines</code> property on the hunk, changing the meaning of the
underlying patch.</p>
</li>
<li>
<p><strong>Git-style patches are now supported by
<code>parsePatch</code>, <code>formatPatch</code>, and
<code>reversePatch</code></strong>.</p>
<p>Patches output by <code>git diff</code> can include some features
that are unlike those output by GNU <code>diff</code>, and therefore not
handled by an ordinary unified diff format parser. An ordinary diff
simply describes the differences between the <em>content</em> of two
files, but Git diffs can also indicate, via &quot;extended
headers&quot;, the creation or deletion of (potentially empty) files,
indicate that a file was renamed, and contain information about file
mode changes. Furthermore, when these changes appear in a diff in the
absence of a content change (e.g. when an empty file is created, or a
file is renamed without content changes), the patch will contain no
associated <code>---</code>/<code>+++</code> file headers nor any
hunks.</p>
<p>jsdiff previously did not support parsing Git's extended headers, nor
hunkless patches. Now <code>parsePatch</code> parses some of the
extended headers, parses hunkless Git patches, and can determine
filenames (e.g. from the extended headers) when parsing a patch that
includes no <code>---</code> or <code>+++</code> file headers. The
additional information conveyed by the extended headers we support is
recorded on new fields on the result object returned by
<code>parsePatch</code>. See <code>isGit</code> and subsequent
properties in the docs in the README.md file.</p>
<p><code>formatPatch</code> now outputs extended headers based on these
new Git-specific properties, and <code>reversePatch</code> respects them
as far as possible (with one unavoidable caveat noted in the README.md
file).</p>
</li>
<li>
<p><strong>Unpaired file headers now cause <code>parsePatch</code> to
throw</strong>.</p>
<p>It remains acceptable to have a patch with no file headers whatsoever
(e.g. one that begins with a <code>@@</code> hunk header on the very
first line), but a patch with <em>only</em> a <code>---</code> header or
only a <code>+++</code> header is now considered an error.</p>
</li>
<li>
<p><strong><code>parsePatch</code> is now more tolerant of
&quot;trailing garbage&quot;</strong></p>
<p>That is: after a patch, or between files/indexes in a patch, it is
now acceptable to have arbitrary lines of &quot;garbage&quot; (so long
as they unambiguously have no syntactic meaning - e.g. trailing garbage
that leads with a <code>+</code>, <code>-</code>, or <code> </code> and
thus is interpretable as part of a hunk still triggers a throw).</p>
<p>This means we no longer reject patches output by tools that include
extra data in &quot;garbage&quot; lines not understood by generic
unified diff parsers. (For example, SVN patches can include
&quot;Property changes on:&quot; lines that generic unified diff parsers
should discard as garbage; jsdiff previously threw errors when
encountering them.)</p>
<p>This change brings jsdiff's behaviour more in line with GNU
<code>patch</code>, which is highly permissive of
&quot;garbage&quot;.</p>
</li>
<li>
<p><strong>The <code>oldFileName</code> and <code>newFileName</code>
fields of <code>StructuredPatch</code> are now typed as <code>string |
undefined</code> instead of <code>string</code></strong>. This type
change reflects the (pre-existing) reality that <code>parsePatch</code>
can produce patches without filenames (e.g. when parsing a patch that
simply contains hunks with no file headers).</p>
</li>
</ul>
</blockquote>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a
href="ed13aca03a"><code>ed13aca</code></a>
Update version in package.json and in release notes (<a
href="https://redirect.github.com/kpdecker/jsdiff/issues/683">#683</a>)</li>
<li><a
href="7a49317b50"><code>7a49317</code></a>
Bump dependencies again (<a
href="https://redirect.github.com/kpdecker/jsdiff/issues/682">#682</a>)</li>
<li><a
href="afe5aecad1"><code>afe5aec</code></a>
Add Git support, and otherwise variously improve &amp; fix parsePatch
(and other ...</li>
<li><a
href="2e46779d88"><code>2e46779</code></a>
Fix a typo (<a
href="https://redirect.github.com/kpdecker/jsdiff/issues/679">#679</a>)</li>
<li>See full diff in <a
href="https://github.com/kpdecker/jsdiff/compare/8.0.4...v9.0.0">compare
view</a></li>
</ul>
</details>
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package.json

@@ -67,7 +67,7 @@
   "dependencies": {
     "@agentclientprotocol/sdk": "1.5.0",
     "@anthropic-ai/claude-agent-sdk": "0.3.280",
-    "diff": "^8.0.3",
+    "diff": "9.0.0",
     "zod": "4.6.5"
   },
   "devDependencies": {