refactor(frontend): improve API and component handling

优化文件内容组件和API工具函数，改进错误处理和配置管理。

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

src/utils/config.js

@@ -9,4 +9,5 @@ export const CONVERT_URL = import.meta.env.VITE_CONVERT_URL || `${API_BASE_URL}/
 export const EXPORT_PDF_URL = import.meta.env.VITE_EXPORT_PDF_URL || '/v1/export/pdf'
 export const TTS_URL = import.meta.env.VITE_TTS_URL || `${API_BASE_URL}/v1/tts-asr/tts`
 export const TTS_STATUS_URL = import.meta.env.VITE_TTS_STATUS_URL || `${API_BASE_URL}/v1/tts-asr/status`
+export const TTS_CONFIG_URL = import.meta.env.VITE_TTS_CONFIG_URL || `${API_BASE_URL}/v1/tts-asr/config`
 export const API_KEY = import.meta.env.VITE_API_KEY || 'your-secret-key-here'