fix: preserve deprecation codes in table of contents

.changeset/tidy-deprecations-smile.md

@@ -0,0 +1,5 @@
+---
+'@node-core/doc-kit': patch
+---
+
+Preserve deprecation codes in generated table-of-contents labels.

src/generators/jsx-ast/utils/__tests__/buildBarProps.test.mjs

@@ -116,6 +116,28 @@ describe('extractHeadings', () => {
     assert.equal(result[1].value, 'new Buffer');
   });
 
+  it('preserves deprecation codes in heading labels', () => {
+    const entries = [
+      {
+        heading: {
+          depth: 2,
+          data: {
+            text: 'DEP0001: `http.OutgoingMessage.prototype.flush`',
+            name: 'http.OutgoingMessage.prototype.flush',
+            slug: 'DEP0001',
+          },
+        },
+      },
+    ];
+
+    const result = extractHeadings(entries);
+
+    assert.equal(
+      result[0].value,
+      'DEP0001: http.OutgoingMessage.prototype.flush'
+    );
+  });
+
   it('drops overload headings and links to the first signature', () => {
     const entries = [
       {

src/generators/jsx-ast/utils/buildBarProps.mjs

@@ -60,8 +60,9 @@ const headingLabel = data => {
     data.text
       // Remove any containing code blocks
       .replace(/`/g, '')
-      // Remove any prefixes (i.e. 'Class:')
-      .replace(/^[^:]+:/, '')
+      // Remove any prefixes (i.e. 'Class:'), except deprecation codes
+      // (i.e. 'DEP0001:') which are part of the label
+      .replace(/^(?!DEP\d+:)[^:]+:/, '')
       // Trim the remaining whitespace
       .trim()
   );