Remove model type check to construct structured messages

All model types use a normalized, chatml structured message format
This check isn't used since offline model support was dropped.

src/khoj/processor/conversation/utils.py

@@ -23,7 +23,6 @@ from transformers import AutoTokenizer, PreTrainedTokenizer, PreTrainedTokenizer
 from khoj.database.adapters import ConversationAdapters
 from khoj.database.models import (
     ChatMessageModel,
-    ChatModel,
     ClientApplication,
     Intent,
     KhojUser,
@@ -528,11 +527,6 @@ def construct_structured_message(
 
     Assume vision is enabled and chat model provider supports messages in chatml format, unless specified otherwise.
     """
-    if not model_type or model_type in [
-        ChatModel.ModelType.OPENAI,
-        ChatModel.ModelType.GOOGLE,
-        ChatModel.ModelType.ANTHROPIC,
-    ]:
     constructed_messages: List[dict[str, Any]] = []
     if not is_none_or_empty(message):
         constructed_messages += [{"type": "text", "text": message}] if isinstance(message, str) else message
@@ -546,12 +540,6 @@ def construct_structured_message(
             constructed_messages += [{"type": "image_url", "image_url": {"url": image}}]
     return constructed_messages
 
-    message = message if isinstance(message, str) else "\n\n".join(m["text"] for m in message)
-    if not is_none_or_empty(attached_file_context):
-        return f"{attached_file_context}\n\n{message}"
-
-    return message
-
 
 def gather_raw_query_files(
     query_files: Dict[str, str],