feat(api): 集成后端API，实现数据持久化和用户登录

- 新增token管理和用户信息状态，支持基于token的自动登录
- 实现登录或注册接口调用，自动根据URL参数完成身份验证
- 从后端加载交易记录、消息和待办提醒，替代本地缓存读写
- 对交易记录的增删改操作同步到数据库，确保数据一致性
- 对消息和提醒的增删改操作支持服务器同步，提升数据可靠性
- 优化消息发送逻辑，先保存用户消息，再处理AI回复并存库
- 添加待办提醒切换状态API调用，确保状态同步服务器
- 改进界面互动，支持文件与头像上传功能，更新管家形象
- 采用异步处理并增加错误捕获和用户提示，增强稳定性

components/EditTransactionModal.tsx

@@ -23,8 +23,8 @@ const EditTransactionModal: React.FC<EditTransactionModalProps> = ({ transaction
   };
 
   return (
-    <div className="fixed inset-0 z-[60] flex items-end md:items-center justify-center bg-black/50 backdrop-blur-sm p-4">
-       <div className="bg-white w-full max-w-md rounded-2xl p-6 shadow-2xl animate-float md:animate-none">
+    <div className="fixed inset-0 z-[60] flex items-end md:items-center justify-center bg-black/50 backdrop-blur-sm p-4 pb-28 md:pb-4">
+       <div className="bg-white w-full max-w-md rounded-2xl p-6 shadow-2xl md:animate-none max-h-[calc(100vh-120px)] overflow-y-auto no-scrollbar">
            <div className="flex justify-between items-center mb-4">
                <h3 className="text-lg font-bold text-gray-900">编辑账单</h3>
                <button onClick={onClose} className="text-gray-400 hover:text-gray-600">

components/LedgerPage.tsx

@@ -6,8 +6,8 @@ import BillReminders, { getDaysRemaining } from './BillReminders';
 
 interface LedgerPageProps {
   transactions: Transaction[];
-  onUpdateTransaction: (t: Transaction) => void;
-  onDeleteTransaction: (id: string) => void;
+  onUpdateTransaction: (t: Transaction) => Promise<void>;
+  onDeleteTransaction: (id: string) => Promise<void>;
   budgets: Record<string, number>;
   setBudgets: (val: Record<string, number>) => void;
   reminders: BillReminder[];
@@ -200,7 +200,24 @@ const LedgerPage: React.FC<LedgerPageProps> = ({
                 {subTab === 'calendar' && <CalendarView transactions={transactions} reminders={reminders} viewDate={selectedMonth} />}
                 {subTab === 'bills' && <BillReminders reminders={reminders.filter(r => r.frequency === 'monthly' || r.targetDate.startsWith(selectedMonth))} onAdd={onAddReminder} onUpdate={onUpdateReminder} onDelete={onDeleteReminder} onToggle={onToggleReminder} />}
           </div>
-          {editingTransaction && <EditTransactionModal transaction={editingTransaction} onSave={(updated) => { onUpdateTransaction(updated); setEditingTransaction(null); }} onDelete={(id) => { onDeleteTransaction(id); setEditingTransaction(null); }} onClose={() => setEditingTransaction(null)} />}
+          {editingTransaction && (
+            <EditTransactionModal 
+              transaction={editingTransaction} 
+              onSave={async (updated) => { 
+                try {
+                  await onUpdateTransaction(updated); 
+                  setEditingTransaction(null); 
+                } catch (e) {
+                  // Error handled in App.tsx
+                }
+              }} 
+              onDelete={async (id) => { 
+                await onDeleteTransaction(id); 
+                setEditingTransaction(null); 
+              }} 
+              onClose={() => setEditingTransaction(null)} 
+            />
+          )}
       </div>
   );
 };

components/VoiceInput.tsx

@@ -11,6 +11,8 @@ const VoiceInput: React.FC<VoiceInputProps> = ({ onTranscript, isProcessing, isF
   const recognitionRef = useRef<any>(null);
   const timerRef = useRef<number | null>(null);
 
+  const isStartingRef = useRef(false);
+
   useEffect(() => {
     if ('SpeechRecognition' in window || 'webkitSpeechRecognition' in window) {
       const SpeechRecognition = window.SpeechRecognition || window.webkitSpeechRecognition;
@@ -22,30 +24,37 @@ const VoiceInput: React.FC<VoiceInputProps> = ({ onTranscript, isProcessing, isF
       recognitionRef.current.onresult = (event: any) => {
         const transcript = event.results[0][0].transcript;
         if (transcript) onTranscript(transcript);
-        setIsListening(false);
       };
 
       recognitionRef.current.onerror = (event: any) => {
+        if (event.error === 'network') {
+          alert("语音识别网络连接失败。请检查网络或尝试切换浏览器（推荐 Chrome/Edge）。");
+        }
         console.error('Speech recognition error', event.error);
-        setIsListening(false);
       };
 
       recognitionRef.current.onend = () => {
         setIsListening(false);
+        isStartingRef.current = false;
       };
     }
   }, [onTranscript]);
 
-  const startListening = (e: React.MouseEvent | React.TouchEvent) => {
-    e.preventDefault();
-    if (isProcessing || isListening) return;
+  const startListening = (e: React.PointerEvent) => {
+    if (e.cancelable) e.preventDefault();
+    
+    if (isProcessing || isListening || isStartingRef.current) return;
 
     if (recognitionRef.current) {
       try {
+        isStartingRef.current = true;
         recognitionRef.current.start();
         setIsListening(true);
-      } catch (e) {
-        console.error("Failed to start recognition", e);
+      } catch (err) {
+        console.error("Failed to start recognition", err);
+        // 如果 start 失败，立即重置状态，否则会锁死
+        isStartingRef.current = false;
+        setIsListening(false);
       }
     } else {
       alert("您的浏览器不支持语音识别，请使用 Chrome 或 Edge。");
@@ -53,20 +62,23 @@ const VoiceInput: React.FC<VoiceInputProps> = ({ onTranscript, isProcessing, isF
   };
 
   const stopListening = () => {
+    // 仅在识别引擎正在运行时尝试停止
+    // 不要在这里重置 isListening 和 isStartingRef，等待 onend 回调
     if (isListening) {
-      recognitionRef.current?.stop();
-      setIsListening(false);
+      try {
+        recognitionRef.current?.stop();
+      } catch (err) {
+        console.error("Failed to stop recognition", err);
+      }
     }
   };
 
   return (
     <div className={`${isFullWidth ? 'w-full' : ''} relative select-none touch-none`}>
       <button
-        onMouseDown={startListening}
-        onMouseUp={stopListening}
-        onMouseLeave={stopListening}
-        onTouchStart={startListening}
-        onTouchEnd={stopListening}
+        onPointerDown={startListening}
+        onPointerUp={stopListening}
+        onPointerLeave={stopListening}
         disabled={isProcessing}
         className={`relative flex items-center justify-center transition-all duration-300 active:scale-95 shadow-lg ${
           isFullWidth