fix: clear localStorage when creating new session

- Added localStorage.removeItem(SESSION_STORAGE_KEY) to handleNewSession
- Prevents old messages from reappearing after page refresh
- New session now starts completely clean

src/views/SearchView.vue

@@ -826,6 +826,9 @@ async function handleNewSession() {
     console.log('[handleNewSession] No current session or no messages to save')
   }
   
+  // Clear localStorage so old messages don't reappear on refresh
+  localStorage.removeItem(SESSION_STORAGE_KEY)
+  
   // Create new session
   const now = new Date()
   const timeStr = `${now.getFullYear()}/${(now.getMonth()+1).toString().padStart(2,'0')}/${now.getDate().toString().padStart(2,'0')} ${now.getHours().toString().padStart(2,'0')}:${now.getMinutes().toString().padStart(2,'0')}`