fix: append trailing slash in manifest (#1486)

Author: Philipp Zerelles

packages/kit/src/core/create_manifest_data/index.js

@@ -204,7 +204,9 @@ export default function create_manifest_data({ config, output, cwd = process.cwd
 				b.splice(i + 1);
 
 				const path = segments.every((segment) => segment.length === 1 && !segment[0].dynamic)
-					? `/${segments.map((segment) => segment[0].content).join('/')}`
+					? `/${segments.map((segment) => segment[0].content).join('/')}${
+							config.kit.trailingSlash === 'always' && segments.length > 0 ? '/' : ''
+					  }`
 					: null;
 
 				routes.push({