fix: 修复统计报表在移动端的溢出问题

- MileageModule 减少移动端 padding (p-6→p-3)
- StatisticsView 添加 overflow-x-hidden 防止横向溢出
- 图表容器添加 overflow-hidden
- 减少图表右侧 margin 防止标签被截断

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/modules/mileage/MileageModule.tsx

@@ -9,8 +9,8 @@ export default function MileageModule() {
   const [activeSubTab, setActiveSubTab] = useState<'monitoring' | 'statistics' | 'report'>('monitoring');
 
   return (
-    <div className="min-h-screen bg-[#F8F9FB] text-gray-800 font-sans p-6 relative">
-      <div className="max-w-6xl mx-auto flex flex-col gap-3 pb-16 px-1 landscape:pb-0 landscape:h-full landscape:flex-1 landscape:overflow-hidden">
+    <div className="min-h-screen bg-[#F8F9FB] text-gray-800 font-sans p-3 md:p-6 relative overflow-x-hidden">
+      <div className="max-w-6xl mx-auto flex flex-col gap-3 pb-16 landscape:pb-0 landscape:h-full landscape:flex-1 landscape:overflow-hidden">
         {/* Sub-navigation */}
         <div className="bg-white px-4 py-2 rounded-2xl border border-slate-100 shadow-sm flex items-center gap-6">
           <button