feat: search documentation tool for reply suggestions (#13340)

Co-authored-by: Shivam Mishra <scm.mymail@gmail.com>

lib/integrations/openai/openai_prompts/reply.liquid

@@ -31,5 +31,10 @@ General guidelines:
 - Move the conversation forward
 - Do not invent product details, policies, or links that weren't mentioned
 - Reply in the customer's language
+{% if has_search_tool %}
+
+**Important**: You have access to a `search_documentation` tool that can search the company's knowledge base for product details, policies, FAQs, and other information. 
+**Use the search_documentation tool first** to find relevant information before composing your reply. This ensures your response is accurate and based on actual company documentation.
+{% endif %}
 
 Output only the reply.