fix(web): 首页只留下载、去登录/在线体验入口; 下载区改二维码; 修复网络版一直提示新版本

- Landing: 移除 header 登录/进入应用按钮、hero 在线体验入口
- 下载区: 复制链接行改为 qrcode.react 二维码 (扫码下载 APK)
- 修复 '持续提示新版本可用' bug: vite 构建时把 BUILD_ID 写入 dist/.build-id,
  manifest-web 返回当前部署 dist 的 build_id, 与浏览器内置值同源比对;
  此前返回 OTA 包 build_id (seq-<ts>) 与页面 BUILD_ID 永不一致 → 横幅常驻

src/pages/Landing.tsx

@@ -1,6 +1,5 @@
 import React, { useEffect, useState } from "react";
-import { useNavigate, Link } from "react-router-dom";
-import { useAppStore } from "../stores/app";
+import { QRCodeSVG } from "qrcode.react";
 import { APP_VERSION, BUILD_ID } from "../version";
 import { checkOtaUpdate, reloadApp } from "../api/ota";
 
@@ -23,17 +22,6 @@ const STATS = [
 ];
 
 function DownloadSection() {
-  const [copied, setCopied] = useState(false);
-  const copy = async () => {
-    try {
-      await navigator.clipboard.writeText(APK_URL);
-      setCopied(true);
-      setTimeout(() => setCopied(false), 2000);
-    } catch {
-      setCopied(false);
-    }
-  };
-
   return (
     <section style={styles.section}>
       <h2 style={styles.sectionTitle}>下载 Android 版</h2>
@@ -45,13 +33,10 @@ function DownloadSection() {
         <p style={{ fontSize: 12, color: "var(--text-tertiary)", marginTop: 10 }}>
           版本 {APP_VERSION} · Android 8.0+ · 约 30 MB
         </p>
-        <div style={{ marginTop: 16 }}>
-          <p style={{ fontSize: 12, color: "var(--text-tertiary)", marginBottom: 6 }}>或复制下载链接(发给手机打开):</p>
-          <div style={styles.linkRow}>
-            <code style={styles.linkCode}>{APK_URL}</code>
-            <button className="btn btn-secondary" style={{ padding: "6px 12px", fontSize: 12 }} onClick={copy}>
-              {copied ? "已复制 ✓" : "复制"}
-            </button>
+        <div style={{ marginTop: 20 }}>
+          <p style={{ fontSize: 12, color: "var(--text-tertiary)", marginBottom: 10 }}>手机扫码下载:</p>
+          <div style={styles.qrWrap}>
+            <QRCodeSVG value={APK_URL} size={168} level="M" style={{ display: "block" }} />
           </div>
         </div>
         <p style={{ fontSize: 12, color: "var(--text-tertiary)", marginTop: 16, lineHeight: 1.6 }}>
@@ -93,23 +78,13 @@ function WebUpdateBanner() {
 }
 
 export default function Landing() {
-  const navigate = useNavigate();
-  const user = useAppStore((s) => s.user);
-
   return (
     <div style={{ minHeight: "100vh", background: "var(--bg)", color: "var(--text-primary)", userSelect: "text" }}>
       <header style={styles.header}>
-        <Link to="/" style={styles.logo}>
+        <div style={styles.logo}>
           <span style={styles.logoEmoji}>👗</span>
           <span style={{ fontWeight: 700, fontSize: 18 }}>Wardrobe</span>
-        </Link>
-        <button
-          className="btn btn-primary"
-          style={{ padding: "8px 18px", fontSize: 14 }}
-          onClick={() => (user ? navigate("/home") : navigate("/login"))}
-        >
-          {user ? "进入应用" : "登录"}
-        </button>
+        </div>
       </header>
 
       <div style={styles.container}>
@@ -127,9 +102,6 @@ export default function Landing() {
             <a className="btn btn-primary" href={APK_URL} download="wardrobe.apk" style={styles.heroBtn}>
               ⬇️ 下载 Android APK
             </a>
-            <button className="btn btn-secondary" style={styles.heroBtn} onClick={() => navigate("/login")}>
-              在线体验 →
-            </button>
           </div>
         </section>
 
@@ -182,14 +154,13 @@ export default function Landing() {
 
 const styles: Record<string, React.CSSProperties> = {
   header: {
-    display: "flex",
-    alignItems: "center",
-    justifyContent: "space-between",
     maxWidth: 960,
     margin: "0 auto",
     padding: "16px 20px",
+    display: "flex",
+    alignItems: "center",
   },
-  logo: { display: "flex", alignItems: "center", gap: 8, textDecoration: "none", color: "var(--text-primary)" },
+  logo: { display: "flex", alignItems: "center", gap: 8 },
   logoEmoji: { fontSize: 24 },
   container: { maxWidth: 960, margin: "0 auto", padding: "0 20px 60px" },
   hero: { textAlign: "center", padding: "64px 0 48px" },
@@ -211,8 +182,13 @@ const styles: Record<string, React.CSSProperties> = {
     margin: "0 auto",
   },
   downloadBtn: { padding: "14px 32px", fontSize: 16 },
-  linkRow: { display: "flex", alignItems: "center", gap: 8, justifyContent: "center", flexWrap: "wrap" },
-  linkCode: { fontSize: 11, color: "var(--text-secondary)", wordBreak: "break-all" },
+  qrWrap: {
+    display: "inline-flex",
+    padding: 10,
+    background: "#fff",
+    border: "1px solid var(--border)",
+    borderRadius: "var(--radius)",
+  },
   techRow: { display: "flex", gap: 10, justifyContent: "center", flexWrap: "wrap" },
   footer: { textAlign: "center", padding: "24px 16px", fontSize: 12, color: "var(--text-tertiary)" },
 };