fix: add loading indicators to all pages

- 'Loading…' shown in charts/fields/output areas while waiting for server response
- Console + chat: clears loading state on first output line
- Player list: table body shows loading row until refresh completes
- Player info / Server info: fields show loading until data arrives

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

js/pages/chat.js

@@ -6,7 +6,7 @@ function ChatPage(params, container) {
 
   var html =
     '<div id="ChatController">' +
-      '<div id="chat-output" style="height:600px" class="Output scrollable"></div>' +
+      '<div id="chat-output" style="height:600px" class="Output scrollable text-white-50">Loading…</div>' +
       '<form id="chat-form">' +
         '<input id="chat-input" class="form-control" style="width:100%" placeholder="Type a message...">' +
       '</form>' +
@@ -15,8 +15,10 @@ function ChatPage(params, container) {
 
   var outputEl = document.getElementById('chat-output');
   var inputEl = document.getElementById('chat-input');
+  var firstMessage = true;
 
   function addMessage(msg) {
+    if (firstMessage) { outputEl.innerHTML = ''; outputEl.classList.remove('text-white-50'); firstMessage = false; }
     var div = document.createElement('div');
     var t = new Date((msg.Time || 0) * 1000);
     var timeStr = t.toLocaleTimeString([], { hour: '2-digit', minute: '2-digit' });