feat: add site onboarding route

src/pages/site/page.tsx

@@ -0,0 +1,64 @@
+import { useEffect, useState } from "react";
+import { useSiteStore } from "@/managers/stores/useSiteStore";
+import { SiteDisclaimerScreen } from "@/components/site/SiteDisclaimerScreen";
+import { SiteWelcomeScreen } from "@/components/site/SiteWelcomeScreen";
+import { SiteSituationScreen } from "@/components/site/SiteSituationScreen";
+import { SiteNamingScreen } from "@/components/site/SiteNamingScreen";
+import { SiteTransitionOverlay } from "@/components/site/SiteTransitionOverlay";
+import { SiteMobileBlocker } from "@/components/site/SiteMobileBlocker";
+import { SiteLayout } from "@/components/site/SiteLayout";
+
+/**
+ * Check if user is on mobile device
+ */
+function useIsMobile(): boolean {
+  const [isMobile, setIsMobile] = useState(false);
+
+  useEffect(() => {
+    const checkMobile = (): void => {
+      const userAgent = navigator.userAgent.toLowerCase();
+      const mobileKeywords = [
+        "android",
+        "webos",
+        "iphone",
+        "ipad",
+        "ipod",
+        "blackberry",
+        "windows phone",
+      ];
+      const isMobileDevice = mobileKeywords.some((keyword) =>
+        userAgent.includes(keyword),
+      );
+      const isSmallScreen = window.innerWidth < 768;
+      setIsMobile(isMobileDevice || isSmallScreen);
+    };
+
+    checkMobile();
+    window.addEventListener("resize", checkMobile);
+    return () => window.removeEventListener("resize", checkMobile);
+  }, []);
+
+  return isMobile;
+}
+
+export function SitePage(): React.JSX.Element {
+  const currentStep = useSiteStore((state) => state.currentStep);
+  const isMobile = useIsMobile();
+
+  if (isMobile) {
+    return <SiteMobileBlocker />;
+  }
+
+  if (currentStep === "disclaimer") {
+    return <SiteDisclaimerScreen />;
+  }
+
+  return (
+    <SiteLayout>
+      {currentStep === "welcome" && <SiteWelcomeScreen />}
+      {currentStep === "situation" && <SiteSituationScreen />}
+      {currentStep === "naming" && <SiteNamingScreen />}
+      {currentStep === "transition" && <SiteTransitionOverlay />}
+    </SiteLayout>
+  );
+}