perf(desktop): stream drag-upload and improve transfer status UX

desktop-client/src-tauri/src/lib.rs

@@ -620,8 +620,6 @@ async fn api_upload_file(
         .and_then(|name| name.to_str())
         .map(|name| name.to_string())
         .ok_or_else(|| "无法识别文件名".to_string())?;
-
-    let file_bytes = fs::read(&source_path).map_err(|err| format!("读取文件失败: {}", err))?;
     let normalized_target = if target_path.trim().is_empty() {
         "/".to_string()
     } else {
@@ -634,9 +632,15 @@ async fn api_upload_file(
         return Err("API 地址不能为空".to_string());
     }
 
+    // 使用流式 multipart 上传，避免大文件整块读入内存导致占用暴涨。
+    let file_part = reqwest::multipart::Part::file(&source_path)
+        .await
+        .map_err(|err| format!("读取文件失败: {}", err))?
+        .file_name(file_name);
+
     let multipart = reqwest::multipart::Form::new()
         .text("path", normalized_target)
-        .part("file", reqwest::multipart::Part::bytes(file_bytes).file_name(file_name));
+        .part("file", file_part);
 
     let mut request = state
         .client