feat(deploy): 新增 Windows 桌面客户端构建与发布支持

CI 拆成三个 job（mac 构建 Linux/Web、windows 构建 Windows 桌面、mac 发布部署）；新增 compile-windows.sh 用 Flutter 构建并打包为 jiu-windows-x64.zip；release.sh 自动写入 Windows 下载 URL 到 version.yaml 并上传 zip。下载页 Windows 卡片从"敬请期待"改为真实下载按钮，URL 由 API 动态填充。

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

scripts/ci/release.sh

@@ -36,11 +36,16 @@ PYEOF
 
 echo "==> release: release_notes=${RELEASE_NOTES}"
 
-# Update backend/config/version.yaml
-python3 - "${VER}" "${RELEASE_NOTES}" <<'PYEOF'
+# Update backend/config/version.yaml (version, build_number, release_notes, windows URL)
+python3 - "${VER}" "${RELEASE_NOTES}" "${TAG}" "${FORGEJO_URL}" "${GITEA_REPOSITORY}" <<'PYEOF'
 import sys
-ver = sys.argv[1]
+ver   = sys.argv[1]
 notes = sys.argv[2]
+tag   = sys.argv[3]
+furl  = sys.argv[4].rstrip('/')
+repo  = sys.argv[5]
+win_url = f"{furl}/{repo}/releases/download/{tag}/jiu-windows-x64.zip"
+
 lines = []
 with open('backend/config/version.yaml') as f:
     for line in f:
@@ -54,11 +59,13 @@ with open('backend/config/version.yaml') as f:
             lines.append('build_number: ' + str(build) + '\n')
         elif line.startswith('release_notes:'):
             lines.append('release_notes: "' + notes.replace('\\', '\\\\').replace('"', '\\"') + '"\n')
+        elif line.startswith('  windows:'):
+            lines.append('  windows: "' + win_url + '"\n')
         else:
             lines.append(line)
 with open('backend/config/version.yaml', 'w') as f:
     f.writelines(lines)
-print('version.yaml updated to', ver)
+print('version.yaml updated to', ver, '| windows:', win_url)
 PYEOF
 
 # Package configs.tar.gz (includes updated version.yaml)
@@ -115,5 +122,6 @@ upload_asset() {
 upload_asset dist/jiu-server
 upload_asset dist/web.tar.gz
 upload_asset dist/configs.tar.gz
+upload_asset dist/jiu-windows-x64.zip
 
 echo "==> release: done — Release ${TAG} created"