Refactor PCM conversion to return result and sample rate

Updated the FFmpeg adapter interfaces and implementations so that PCM conversion methods now return an object containing the conversion result and sample rate, instead of a Buffer. Adjusted audio processing logic to accommodate this change and improved error logging. Updated native ffmpeg addon binaries.

src/common/ffmpeg-exec-adapter.ts

@@ -157,7 +157,7 @@ export class FFmpegExecAdapter implements IFFmpegAdapter {
     /**
      * 转换为 PCM
      */
-    async convertToPCM(filePath: string, pcmPath: string): Promise<Buffer> {
+    async convertToPCM(filePath: string, pcmPath: string): Promise<{ result: boolean, sampleRate: number }> {
         try {
             ensureDirExists(pcmPath);
 
@@ -174,7 +174,7 @@ export class FFmpegExecAdapter implements IFFmpegAdapter {
                 throw new Error('转换PCM失败，输出文件不存在');
             }
 
-            return readFileSync(pcmPath);
+            return { result: true, sampleRate: 24000 };
         } catch (error: any) {
             throw new Error(`FFmpeg处理转换出错: ${error.message}`);
         }