fix(sync): 移除多线程下载并补齐staging复用回归

infrastructure/src/bin/bat_official_sync.rs

@@ -4471,8 +4471,6 @@ fn daemon_child_args(options: &CliOptions) -> Vec<String> {
     }
     args.push("--curl".to_string());
     args.push(config.curl_command.to_string_lossy().to_string());
-    args.push("--download-concurrency".to_string());
-    args.push(config.download_concurrency.to_string());
     match config.curl_proxy.mode() {
         CurlProxyMode::Auto if options.proxy_option_explicit => {
             args.push("--proxy".to_string());
@@ -4959,9 +4957,6 @@ BAT_AUTO_DISCOVER=1
 # 正常检查间隔与失败重试间隔（秒）
 #BAT_INTERVAL_SECONDS=3600
 #BAT_ERROR_RETRY_SECONDS=60
-# 下载并发度（并行网络下载数，1~256；默认 4，对官方 CDN 礼貌）
-#BAT_DOWNLOAD_CONCURRENCY=4
-
 # ---- 网络 ----
 # 显式代理 URL（支持 http/https/socks4/socks4a/socks5/socks5h）。
 # 不设则自动检测 HTTPS_PROXY / ALL_PROXY / HTTP_PROXY（也可写在本文件里）。
@@ -5145,9 +5140,6 @@ fn apply_bat_env_overrides(
     if let Some(v) = value("BAT_UNZIP") {
         options.config.unzip_command = PathBuf::from(v);
     }
-    if let Some(v) = value("BAT_DOWNLOAD_CONCURRENCY") {
-        options.config.download_concurrency = parse_download_concurrency(&v)?;
-    }
     if let Some(v) = value("BAT_PROXY") {
         options.config.curl_proxy = parse_proxy_config(&v)?;
     }
@@ -5325,11 +5317,6 @@ fn parse_args_with_env(
             "--unzip" => {
                 options.config.unzip_command = PathBuf::from(next_option_value(&mut args, &flag)?);
             }
-            "--download-concurrency" => {
-                let value = next_option_value(&mut args, &flag)?;
-                options.config.download_concurrency = parse_download_concurrency(&value)?;
-                options.sync_option_explicit = true;
-            }
             "--dry-run" => {
                 options.config.dry_run = true;
                 options.sync_option_explicit = true;
@@ -5668,7 +5655,6 @@ fn print_usage(binary: &str) {
     eprintln!("  --proxy <URL|auto|none>          curl proxy override (default: auto from env)");
     eprintln!("  --no-proxy                       Force direct curl connections");
     eprintln!("  --unzip <PATH>                   unzip executable (default: unzip)");
-    eprintln!("  --download-concurrency <N>       Parallel downloads, 1..=256 (default: 4)");
     eprintln!("  --dry-run                        Do not write sync state");
     eprintln!("  --plan                           Include planned URLs in dry-run");
     eprintln!("  --force                          Force download/refresh");
@@ -5743,17 +5729,6 @@ fn parse_platforms(value: &str) -> Result<Vec<PatchPlatform>, String> {
         .collect()
 }
 
-/// 解析下载并发度：正整数，钳制到 `1..=256`。
-fn parse_download_concurrency(value: &str) -> anyhow::Result<usize> {
-    let parsed = value
-        .parse::<usize>()
-        .map_err(|error| anyhow::anyhow!("下载并发度无效：{error}"))?;
-    if parsed == 0 {
-        return Err(anyhow::anyhow!("下载并发度必须大于 0"));
-    }
-    Ok(parsed.min(256))
-}
-
 fn parse_platform(value: &str) -> Result<PatchPlatform, String> {
     match value.to_ascii_lowercase().as_str() {
         "windows" | "win" => Ok(PatchPlatform::Windows),
@@ -6036,51 +6011,6 @@ mod tests {
         assert_eq!(registry.get("task-1-2").unwrap().status, "succeeded");
     }
 
-    #[test]
-    fn parses_download_concurrency_flag_and_env() {
-        // 默认值（与 OfficialUpdateConfig 默认一致）。
-        assert_eq!(
-            parse(&["bat"]).unwrap().config.download_concurrency,
-            OfficialUpdateConfig::default().download_concurrency
-        );
-        // CLI 显式设置 + 上限钳制。
-        assert_eq!(
-            parse(&["bat", "--download-concurrency", "16"])
-                .unwrap()
-                .config
-                .download_concurrency,
-            16
-        );
-        assert_eq!(
-            parse(&["bat", "--download-concurrency", "9999"])
-                .unwrap()
-                .config
-                .download_concurrency,
-            256
-        );
-        // 0 与非数字报错。
-        assert!(parse(&["bat", "--download-concurrency", "0"]).is_err());
-        assert!(parse(&["bat", "--download-concurrency", "abc"]).is_err());
-        // 环境变量（含 .env）设置默认值；CLI 覆盖之。
-        assert_eq!(
-            parse_with_env(&["bat"], &[("BAT_DOWNLOAD_CONCURRENCY", "12")])
-                .unwrap()
-                .config
-                .download_concurrency,
-            12
-        );
-        assert_eq!(
-            parse_with_env(
-                &["bat", "--download-concurrency", "3"],
-                &[("BAT_DOWNLOAD_CONCURRENCY", "12")]
-            )
-            .unwrap()
-            .config
-            .download_concurrency,
-            3
-        );
-    }
-
     #[test]
     fn parses_auto_discover_sync_args() {
         let options = parse(&[
@@ -6326,8 +6256,6 @@ mod tests {
             "http://127.0.0.1:7890",
             "--unzip",
             "/usr/bin/unzip",
-            "--download-concurrency",
-            "40",
             "--interval",
             "30m",
             "--error-retry",
@@ -6350,9 +6278,6 @@ mod tests {
         assert!(args
             .windows(2)
             .any(|pair| pair == ["--platforms", "Windows,Android"]));
-        assert!(args
-            .windows(2)
-            .any(|pair| pair == ["--download-concurrency", "40"]));
         // 代理凭据不得进入子进程 argv：只放不含凭据的 flag，URL 经环境变量下传。
         assert!(args.contains(&PROXY_FROM_ENV_FLAG.to_string()));
         assert!(!args.iter().any(|arg| arg.contains("127.0.0.1:7890")));