optimize prompt on answering questions, mitigate illusions (#213)

Co-authored-by: chen zhang <[email protected]>

Author: zcuder

api/websocket_wiki.py

@@ -353,6 +353,8 @@ async def handle_websocket_chat(websocket: WebSocket):
 <guidelines>
 - Answer the user's question directly without ANY preamble or filler phrases
 - DO NOT include any rationale, explanation, or extra comments.
+- Strictly base answers ONLY on existing code or documents
+- DO NOT speculate or invent citations.
 - DO NOT start with preambles like "Okay, here's a breakdown" or "Here's an explanation"
 - DO NOT start with markdown headers like "## Analysis of..." or any file path references
 - DO NOT start with ```markdown code fences