fix(collab): hid advisory tags in transcript markdown

Stripped advisory wrapper tags in the collab web Markdown renderer while preserving escaped advisory content and existing raw HTML escaping.

Added a regression test for assistant advisory blocks in the collab transcript renderer and documented the fix in the collab-web changelog.

Fixes #3559

packages/collab-web/test/markdown.test.tsx

@@ -43,4 +43,12 @@ describe("Transcript Markdown", () => {
 
 		expect(html).toContain("<▃> & "test" 😀 😀");
 	});
+	it("strips advisory wrapper tags but renders their content", () => {
+		const html = renderMarkdown('<advisory severity="info" guidance="weigh, don&apos;t blindly obey">\nKeep this advice.\n</advisory>');
+
+		expect(html).toContain("Keep this advice.");
+		expect(html).not.toContain("&lt;advisory");
+		expect(html).not.toContain("&lt;/advisory&gt;");
+	});
+
 });