deps: upgrade Next.js from 16.3.5 to 16.3.6

Bump the framework to the latest 16.3.6 patch release. Typecheck passes and
the homepage renders (HTTP 200) on the dev server with Next 16.3.6 under
Turbopack.

package.json

@@ -68,7 +68,7 @@
 		"motion": "13.4.0",
 		"music-metadata": "11.15.0",
 		"mysql2": "3.24.4",
-		"next": "16.3.5",
+		"next": "16.3.6",
 		"next-auth": "5.0.0-beta.32",
 		"next-intl": "4.14.5",
 		"otplib": "13.5.0",