feat: enhance textbook reader with anchor text support and improve knowledge point management

src/app/(dashboard)/teacher/classes/my/page.tsx

@@ -15,16 +15,7 @@ async function MyClassesPageImpl() {
   const classes = await getTeacherClasses()
 
   return (
-    <div className="flex h-full flex-col space-y-8 p-8">
-      <div className="flex flex-col justify-between space-y-4 md:flex-row md:items-center md:space-y-0">
-        <div>
-          <h2 className="text-2xl font-bold tracking-tight">My Classes</h2>
-          <p className="text-muted-foreground">
-            Overview of your classes.
-          </p>
-        </div>
-      </div>
-
+    <div className="flex h-full flex-col space-y-4 p-8">
       <MyClassesGrid classes={classes} canCreateClass={false} />
     </div>
   )