feat: enhance error handling and reasoning mechanisms across middleware

- Improve error handling across multiple middleware and adapter components, ensuring consistent error response formats in JSON.
- Enhance the functionality of request conversion functions by including context parameters and robust error wrapping.
- Introduce new features related to reasoning content in the messaging model, providing better customization and explanations in the documentation.

relay/adaptor/doubao/main.go

@@ -2,6 +2,8 @@ package doubao
 
 import (
 	"fmt"
+	"strings"
+
 	"github.com/songquanpeng/one-api/relay/meta"
 	"github.com/songquanpeng/one-api/relay/relaymode"
 )