feat: add support for audio and video input via base64

This commit adds configuration and conversion logic to handle audio and video inputs in base64 format, similar to existing image support. It includes:

1. Added supported formats and size limits in config
2. Implemented media validation and conversion in message converter
3. Updated payload building to handle media parts
4. Improved error handling and logging for media processing

app/config/config.py

@@ -69,6 +69,12 @@ class Settings(BaseSettings):
     # 日志配置
     LOG_LEVEL: str = "INFO" # 默认日志级别
 
+    # Audio/Video Settings
+    SUPPORTED_AUDIO_FORMATS: List[str] = ["wav", "mp3", "flac", "ogg"] # Add formats Gemini supports
+    SUPPORTED_VIDEO_FORMATS: List[str] = ["mp4", "mov", "avi", "webm"] # Add formats Gemini supports
+    MAX_AUDIO_SIZE_BYTES: int = 50 * 1024 * 1024  # Example: 50MB limit for Base64 payload
+    MAX_VIDEO_SIZE_BYTES: int = 200 * 1024 * 1024 # Example: 200MB limit
+
     def __init__(self, **kwargs):
         super().__init__(**kwargs)
         # 设置默认AUTH_TOKEN（如果未提供）
@@ -78,6 +84,24 @@ class Settings(BaseSettings):
 # 创建全局配置实例
 settings = Settings()
 
+# Optional: Define MIME type mappings if needed, or handle directly in converter
+AUDIO_FORMAT_TO_MIMETYPE = {
+    "wav": "audio/wav",
+    "mp3": "audio/mpeg",
+    "flac": "audio/flac",
+    "ogg": "audio/ogg",
+    # Add other mappings supported by Gemini
+}
+
+VIDEO_FORMAT_TO_MIMETYPE = {
+    "mp4": "video/mp4",
+    "mov": "video/quicktime",
+    "avi": "video/x-msvideo",
+    "webm": "video/webm",
+     # Add other mappings supported by Gemini
+}
+
+
 def _parse_db_value(key: str, db_value: str, target_type: Type) -> Any:
     """尝试将数据库字符串值解析为目标 Python 类型"""
     from app.log.logger import get_config_logger # 函数内导入