feat: 新增引导式新手指引 (OnboardingTour) 组件，全站页面接入

src/App.tsx

@@ -375,6 +375,7 @@ function App() {
 
   const [ecommerceEverMounted, setEcommerceEverMounted] = useState(false);
   const [workbenchResetToken, setWorkbenchResetToken] = useState(0);
+  const [onboardingActive, setOnboardingActive] = useState(false);
   const isEcommerceActive = activeView === "ecommerce" || activeView === "ecommerceHub";
   useEffect(() => {
     if (isEcommerceActive && !ecommerceEverMounted) setEcommerceEverMounted(true);
@@ -473,6 +474,17 @@ function App() {
     }
   }, [session, setView, setWorkspaceExpanded]);
 
+  const handleStartOnboarding = useCallback(() => {
+    setOnboardingActive(true);
+    try { window.localStorage.setItem("omniai:onboarding", "1"); } catch {}
+    handleSetView("workbench");
+  }, [handleSetView]);
+
+  const handleEndOnboarding = useCallback(() => {
+    setOnboardingActive(false);
+    try { window.localStorage.removeItem("omniai:onboarding"); } catch {}
+  }, []);
+
   const clearAuthenticatedState = useCallback((options?: { resetView?: boolean }) => {
     clearAllUserStorage();
     clearSessionState();
@@ -1320,6 +1332,8 @@ function App() {
             key={`workbench-${workbenchResetToken}`}
             isAuthenticated={Boolean(session)}
             session={session}
+            onboarding={onboardingActive}
+            onEndOnboarding={handleEndOnboarding}
             onRequireLogin={handleRequireTaskLogin}
             onOpenResultInCanvas={handleOpenResultInCanvas}
             onRefreshUsage={refreshUsage}
@@ -1330,6 +1344,7 @@ function App() {
         return (
           <HomePage
             onOpenGenerate={() => handleSetView("workbench")}
+            onStartOnboarding={handleStartOnboarding}
             onOpenCanvas={() => handleSetView("canvas")}
             onOpenEcommerce={() => handleSetView("ecommerce")}
             onOpenScriptReview={() => handleSetView("scriptTokens")}