fix(ci): restore full localized sitemap coverage and strict 404 validation

scripts/check-html.ts

@@ -48,12 +48,13 @@ async function main() {
       try {
         const res = await axios.get(u, {
           headers: { Cookie: `klz_gatekeeper_session=${gatekeeperPassword}` },
+          validateStatus: (status) => status < 400,
         });
         const filename = `page-${i}.html`;
         fs.writeFileSync(path.join(outputDir, filename), res.data);
       } catch (err: any) {
         console.error(`❌ HTTP Error fetching ${u}: ${err.message}`);
-        throw err;
+        throw new Error(`Failed to fetch page: ${u} - ${err.message}`);
       }
     }