feat(base): 添加单任务内文件传输并发功能

- 引入 ThreadPoolExecutor 实现并行下载和上传
- 新增 download_files_parallel 和 upload_files_parallel 方法
- 添加任务传输并发数配置选项 TASK_DOWNLOAD_CONCURRENCY 和 TASK_UPLOAD_CONCURRENCY
- 实现并发数配置的环境变量解析和验证逻辑
- 在多个处理器中应用并行下载优化文件获取性能
- 更新 .env.example 配置文件模板
- 移除 FFmpeg 命令日志长度限制

handlers/package_ts.py

@@ -81,29 +81,43 @@ class PackageSegmentTsHandler(BaseHandler):
             start_sec = start_time_ms / 1000.0
             duration_sec = duration_ms / 1000.0
 
-            # 1. 下载视频片段
+            # 1. 并行下载视频片段与全局音频
             video_file = os.path.join(work_dir, 'video.mp4')
-            if not self.download_file(video_url, video_file):
+            audio_file = os.path.join(work_dir, 'audio.aac')
+            download_results = self.download_files_parallel([
+                {
+                    'key': 'video',
+                    'url': video_url,
+                    'dest': video_file,
+                    'required': True
+                },
+                {
+                    'key': 'audio',
+                    'url': audio_url,
+                    'dest': audio_file,
+                    'required': True
+                }
+            ])
+            video_result = download_results.get('video')
+            if not video_result or not video_result['success']:
                 return TaskResult.fail(
                     ErrorCode.E_INPUT_UNAVAILABLE,
                     f"Failed to download video: {video_url}"
                 )
-
-            # 2. 下载全局音频
-            audio_file = os.path.join(work_dir, 'audio.aac')
-            if not self.download_file(audio_url, audio_file):
+            audio_result = download_results.get('audio')
+            if not audio_result or not audio_result['success']:
                 return TaskResult.fail(
                     ErrorCode.E_INPUT_UNAVAILABLE,
                     f"Failed to download audio: {audio_url}"
                 )
 
-            # 3. 判断是否需要精确裁剪视频
+            # 2. 判断是否需要精确裁剪视频
             needs_video_trim = not is_transition_segment and (
                 (trim_head and trim_head_ms > 0) or
                 (trim_tail and trim_tail_ms > 0)
             )
 
-            # 4. 如果需要裁剪，先重编码裁剪视频
+            # 3. 如果需要裁剪，先重编码裁剪视频
             processed_video_file = video_file
             if needs_video_trim:
                 processed_video_file = os.path.join(work_dir, 'trimmed_video.mp4')
@@ -129,7 +143,7 @@ class PackageSegmentTsHandler(BaseHandler):
                         "Trimmed video file is missing or too small"
                     )
 
-            # 5. 构建 TS 封装命令
+            # 4. 构建 TS 封装命令
             output_file = os.path.join(work_dir, 'segment.ts')
             cmd = self._build_package_command(
                 video_file=processed_video_file,
@@ -139,14 +153,14 @@ class PackageSegmentTsHandler(BaseHandler):
                 duration_sec=duration_sec
             )
 
-            # 6. 执行 FFmpeg
+            # 5. 执行 FFmpeg
             if not self.run_ffmpeg(cmd, task.task_id):
                 return TaskResult.fail(
                     ErrorCode.E_FFMPEG_FAILED,
                     "TS packaging failed"
                 )
 
-            # 7. 验证输出文件
+            # 6. 验证输出文件
             if not self.ensure_file_exists(output_file, min_size=1024):
                 return TaskResult.fail(
                     ErrorCode.E_FFMPEG_FAILED,