Revert "Merge"

This reverts commit abb1e3f52d.

app/MindWork AI Studio/Provider/OpenAI/ProviderOpenAI.cs

@@ -76,6 +76,7 @@ public sealed class ProviderOpenAI(ILogger logger) : BaseProvider("https://api.o
                     ChatRole.USER => "user",
                     ChatRole.AI => "assistant",
                     ChatRole.AGENT => "assistant",
+                    ChatRole.RAG => "assistant",
                     ChatRole.SYSTEM => systemPromptRole,
 
                     _ => "user",