fix(welcome): 欢迎页沿用站点外观与 SEO 标题

合并 #683：欢迎页沿用站点外观与 SEO 标题

web/src/main.tsx

@@ -7,8 +7,10 @@ import { isIsolatedPrevisRepro } from "@/lib/dev-repro";
 installChunkRecovery();
 
 // The public film entry checks its availability independently of workspace bootstrap.
-if (/^\/welcome\/?$/.test(window.location.pathname)) void import("./welcome-application");
-else {
+if (/^\/welcome\/?$/.test(window.location.pathname)) {
+    void bootstrapAppearance().catch(() => undefined);
+    void import("./welcome-application");
+} else {
     // The backend-free DEV lab must not make requests before AppProviders isolates it.
     const appearanceReady = isIsolatedPrevisRepro(import.meta.env.DEV, window.location.pathname) ? Promise.resolve() : bootstrapAppearance();
     void import("./application");