prompt adjustement

prompts.py

@@ -15,6 +15,7 @@ OPPORTUNITY_PROMPT = (
     "- Return ONLY the JSON object inside markdown backticks (```json ... ```).\n"
     "- Do NOT include any introductory or conversational text.\n"
     "- If a field is missing, use 'N/A'.\n\n"
+    "- 'type' must be one of the following: Residency, Open Call, Funding, Workshop.\n\n"
     "# EXAMPLE OUTPUT\n"
     "```json\n"
     "{\n"