more refactor in frontend javascript

web/js/window.js

@@ -0,0 +1,27 @@
+// Check for saved session on page load
+window.addEventListener("DOMContentLoaded", function () {
+  const savedToken = localStorage.getItem("chatToken");
+  const savedUsername = localStorage.getItem("chatUsername");
+  const savedPhone = localStorage.getItem("chatUserPhone");
+
+  if (savedToken && savedUsername) {
+    currentUserPhone = savedPhone;
+    validateToken(savedToken, savedUsername);
+  }
+
+  // Auto-resize textarea
+  const messageInput = document.getElementById("messageInput");
+  messageInput.addEventListener("input", function () {
+    this.style.height = "auto";
+    this.style.height = Math.min(this.scrollHeight, 100) + "px";
+  });
+
+  // Update mobile detection on resize
+  window.addEventListener("resize", function () {
+    isMobile = window.innerWidth <= 768;
+    if (!isMobile) {
+      // On desktop, ensure chats panel is visible
+      document.getElementById("chatsPanel").classList.remove("active");
+    }
+  });
+});