feat(client): Windows 提供 Inno Setup 安装程序 + 下载改同源 HTTPS

- Windows 客户端打成 jiu-windows-x64-setup.exe（Inno Setup，中文向导、
  桌面/开始菜单快捷方式、卸载项），替代解压版 zip
- provision-windows.sh 自动静默安装 Inno Setup（缺则装）
- 下载 URL 从内网 HTTP Forgejo 改为 https://jiu.51yanmei.com/downloads/，
  修复 HTTPS 页面下发 http 内网地址被浏览器拦截（无法安全下载），win/mac 均生效
- deploy.sh 将安装包发布到 EC2 /opt/jiu/downloads/，nginx 新增 /downloads/ 路由

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

deploy/nginx-jiu.conf

@@ -59,6 +59,14 @@ server {
         try_files /scan.html =404;
     }
 
+    # 桌面客户端安装包下载（Windows .exe / macOS .zip）
+    location /downloads/ {
+        alias /opt/jiu/downloads/;
+        add_header Content-Disposition "attachment";
+        add_header Cache-Control "no-cache";
+        autoindex off;
+    }
+
     # 营销站点兜底（根路径及所有其他路径）
     location / {
         root /opt/jiu/marketing;

deploy/windows/jiu-installer.iss

@@ -0,0 +1,53 @@
+; Inno Setup script for 岩美酒库 Windows 客户端
+; Compiled in CI:
+;   ISCC /DAppVer=<ver> "/DSrcDir=<ReleaseDir>" "/DOutDir=<dist>" jiu-installer.iss
+; Produces: <OutDir>\jiu-windows-x64-setup.exe
+
+#ifndef AppVer
+  #define AppVer "0.0.0"
+#endif
+#ifndef SrcDir
+  #define SrcDir "."
+#endif
+#ifndef OutDir
+  #define OutDir "."
+#endif
+
+#define MyAppName "岩美酒库"
+#define MyAppExe "jiu_client.exe"
+#define MyAppPublisher "岩美"
+
+[Setup]
+AppId={{A3F5C1E2-9B47-4D8A-B6E0-2C1D4F8A9E33}
+AppName={#MyAppName}
+AppVersion={#AppVer}
+AppPublisher={#MyAppPublisher}
+DefaultDirName={autopf}\Jiu
+DefaultGroupName={#MyAppName}
+DisableProgramGroupPage=yes
+OutputDir={#OutDir}
+OutputBaseFilename=jiu-windows-x64-setup
+Compression=lzma2
+SolidCompression=yes
+WizardStyle=modern
+ArchitecturesAllowed=x64
+ArchitecturesInstallIn64BitMode=x64
+UninstallDisplayName={#MyAppName}
+UninstallDisplayIcon={app}\{#MyAppExe}
+
+[Languages]
+Name: "chinesesimp"; MessagesFile: "compiler:Languages\ChineseSimplified.isl"
+
+[Tasks]
+Name: "desktopicon"; Description: "{cm:CreateDesktopIcon}"; GroupDescription: "{cm:AdditionalIcons}"; Flags: checkedonce
+
+[Files]
+Source: "{#SrcDir}\*"; DestDir: "{app}"; Flags: recursesubdirs createallsubdirs ignoreversion
+
+[Icons]
+Name: "{group}\{#MyAppName}"; Filename: "{app}\{#MyAppExe}"
+Name: "{group}\卸载 {#MyAppName}"; Filename: "{uninstallexe}"
+Name: "{commondesktop}\{#MyAppName}"; Filename: "{app}\{#MyAppExe}"; Tasks: desktopicon
+
+[Run]
+Filename: "{app}\{#MyAppExe}"; Description: "{cm:LaunchProgram,{#MyAppName}}"; Flags: nowait postinstall skipifsilent