加字体大小设置，修复人工客服轮询和限流问题

templates/index.html

@@ -1202,6 +1202,7 @@
             <span><span class="ai-icon">🤖</span><span id="app-title">柏悦物流智能助手</span></span>
             <span class="title-actions">
                 <button id="lang-toggle" class="theme-toggle lang-toggle" title="中英文切换（Ctrl+L）">中</button>
+                <button id="font-toggle" class="theme-toggle" title="字体大小">A</button>
                 <button id="theme-toggle" class="theme-toggle" title="切换深色/浅色">🌙</button>
             </span>
         </div>
@@ -1361,6 +1362,27 @@ window.__busy = false;   // 生成中状态，用 window 属性避免作用域
     }
 })();
 
+// ===== 字体大小切换 =====
+(function(){
+    var KEY = "wuliu-fontsize";
+    var SIZES = [14, 16, 18, 20];
+    var idx = 1;
+    try{ var s = localStorage.getItem(KEY); if(s) idx = parseInt(s); }catch(e){}
+    var btn = document.getElementById("font-toggle");
+    function apply(){
+        document.body.style.fontSize = SIZES[idx] + "px";
+        if(btn) btn.textContent = SIZES[idx] + "px";
+    }
+    apply();
+    if(btn){
+        btn.onclick = function(){
+            idx = (idx + 1) % SIZES.length;
+            apply();
+            try{ localStorage.setItem(KEY, idx); }catch(e){}
+        };
+    }
+})();
+
 // ===== 中英文切换 =====
 const I18N = {
     zh: {
@@ -1872,62 +1894,56 @@ window.showHuman = async function(){
         addMsg("您已在人工客服会话中，请直接提问。", false);
         return;
     }
-    const now = new Date();
-    const day = now.getDay();
-    const h = now.getHours();
-    const work = (day >= 1 && day <= 5) && (h >= 9 && h < 18);
+    var now = new Date();
+    var day = now.getDay();
+    var h = now.getHours();
+    var work = (day >= 1 && day <= 5) && (h >= 9 && h < 19);
     if(!work){
         addMsg("人工客服工作时间：周一至周五 9:00-18:00\n当前非工作时间，留言后工作时间内会尽快回复。", false);
         return;
     }
     addMsg("正在为您转接人工客服...", false);
-    if(!currentConvId) await ensureConv();
-    fetch("/api/human/request",{method:"POST",headers:{"Content-Type":"application/json"},body:JSON.stringify({conv_id:currentConvId})})
-    .then(r=>r.json()).then(d=>{
+    if(!currentConvId){
+        try{ await ensureConv(); }catch(e){}
+    }
+    fetch("/api/human/request",{method:"POST",headers:{"Content-Type":"application/json"},body:JSON.stringify({conv_id:currentConvId||0})})
+    .then(function(r){return r.json()})
+    .then(function(d){
         if(d.ok){
             window.humanSid = d.session_id;
             addMsg("您已加入人工排队，请稍候...", false);
             startHumanPoll();
+        }else{
+            addMsg("转接失败，请稍后再试。", false);
         }
+    })
+    .catch(function(){
+        addMsg("网络错误，请稍后再试。", false);
     });
 }
 window.humanSid = 0;
 function startHumanPoll(){
     let last=0;
-    let typingShown=null;
     const t=setInterval(()=>{
         if(!window.humanSid){ clearInterval(t); return; }
-        fetch("/api/human/poll?sid="+window.humanSid+"&after="+last).then(r=>r.json()).then(d=>{
+        fetch("/api/human/poll?sid="+window.humanSid+"&after="+last)
+        .then(r=>r.json())
+        .then(d=>{
             if(d.status==="closed"){
                 clearInterval(t);
                 window.humanSid=0;
                 window.__busy=false;
                 if(typeof setBusy==="function") setBusy(false);
                 addMsg("人工客服已结束，您可以继续向 AI 提问。", false);
-                inputDom.focus();
                 return;
             }
-            if(typingShown){ typingShown.remove(); typingShown=null; }
-            if(d.typing){
-                typingShown = addMsg("对方正在输入...", false);
-            }
             d.messages.forEach(m=>{
                 last=m.id;
-                if(m.side==="agent"){
-                    addMsg(m.content, false);
-                }
+                if(m.side==="agent") addMsg(m.content, false);
             });
-            // 已读回执：标记最后一条用户消息
-            if(d.messages.some(m=>m.side==="customer" && m.read)){
-                const rows=document.querySelectorAll(".msg-row.user-line");
-                if(rows.length){
-                    const last=rows[rows.length-1];
-                    const ts=last.querySelector(".msg-time");
-                    if(ts && !ts.textContent.includes("已读")) ts.textContent += " ✓已读";
-                }
-            }
-        });
-    }, 2000);
+        })
+        .catch(()=>{});
+    }, 1000);
 }
 
 function addMsg(content, isUser){