feat: 防爆破 - 5分钟内密码错3次永久封禁IP

public/app.js

@@ -1203,7 +1203,15 @@
           document.dispatchEvent(new CustomEvent('cc-web-auth-failed'));
           loginOverlay.hidden = false;
           app.hidden = true;
-          loginError.hidden = false;
+          if (msg.banned) {
+            loginError.textContent = '该 IP 已被永久封禁';
+            loginError.hidden = false;
+            loginPassword.disabled = true;
+            loginForm.querySelector('button[type="submit"]').disabled = true;
+          } else {
+            loginError.textContent = '密码错误';
+            loginError.hidden = false;
+          }
         }
         break;
 

public/style.css

@@ -1016,12 +1016,10 @@ body.session-loading-active {
 .msg.user .msg-avatar { background: var(--bg-bubble-user); color: #fff; }
 .msg.assistant .msg-avatar { background: var(--success); color: #fff; }
 .msg-avatar svg { display: block; flex-shrink: 0; }
-/* Claude avatar: transparent bg, pixel crab uses theme accent color */
+/* Claude avatar: transparent bg, fixed-color pixel crab */
 .msg.assistant.agent-claude .msg-avatar {
   background: transparent;
-  color: var(--accent);
-  border: 1.5px solid var(--accent);
-  font-size: 18px;
+  border: none;
 }
 /* Codex avatar: GPT logo on green bg */
 .msg.assistant.agent-codex .msg-avatar {