feat: add developer role (#936)

chat.go

@@ -14,6 +14,7 @@ const (
 	ChatMessageRoleAssistant = "assistant"
 	ChatMessageRoleFunction  = "function"
 	ChatMessageRoleTool      = "tool"
+	ChatMessageRoleDeveloper = "developer"
 )
 
 const chatCompletionsSuffix = "/chat/completions"

reasoning_validator.go

@@ -35,6 +35,7 @@ var unsupportedToolsForO1Models = map[ToolType]struct{}{
 var availableMessageRoleForO1Models = map[string]struct{}{
 	ChatMessageRoleUser:      {},
 	ChatMessageRoleAssistant: {},
+	ChatMessageRoleDeveloper: {},
 }
 
 // ReasoningValidator handles validation for o-series model requests.