feat: 重构页面、路由与业务组件，新增课程演示

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/pages/CourseDemo/CourseDemoGuideSpotlight.tsx

@@ -0,0 +1,15 @@
+import { GuideSpotlight } from "@/components/common";
+import { CourseDemoGuideSpotlightPanel } from "./CourseDemoGuideSpotlightPanel";
+
+export function CourseDemoGuideSpotlight() {
+	return (
+		<GuideSpotlight
+			theme={{
+				panelMaxWidth: 620,
+				offset: 20,
+			}}
+		>
+			{(spotlight) => <CourseDemoGuideSpotlightPanel spotlight={spotlight} />}
+		</GuideSpotlight>
+	);
+}