refactor: remove welcome message and associated CSS

Co-authored-by: aider (deepseek/deepseek-chat) <aider@aider.chat>

Author: coding-hui

website/src/pages/index.module.css

@@ -18,22 +18,6 @@
   padding: 1rem;
 }
 
-.welcomeMessage {
-  font-size: 1rem;
-  color: #718096;
-  margin-bottom: 1rem;
-}
-
-.wave {
-  animation: wave 2s infinite;
-}
-
-@keyframes wave {
-  0% { transform: rotate(0deg); }
-  25% { transform: rotate(10deg); }
-  75% { transform: rotate(-10deg); }
-  100% { transform: rotate(0deg); }
-}
 
 .heroTitle {
   font-size: 2.5rem;

website/src/pages/index.tsx

@@ -14,9 +14,6 @@ function HomepageHeader() {
     <header className={clsx('hero', styles.heroBanner)}>
       <div className="container">
         <div className={styles.heroContent}>
-          <div className={styles.welcomeMessage}>
-            <span className={styles.wave}>👋</span> Hello!
-          </div>
           <Heading as="h1" className={styles.heroTitle}>
             AI Development Assistant
           </Heading>