Add server_name fallback logic in OpenAI MCP tool registration service

Co-authored-by: pontemonti <7850950+pontemonti@users.noreply.github.com>

Author: Copilot

libraries/microsoft-agents-a365-tooling-extensions-openai/microsoft_agents_a365/tooling/extensions/openai/mcp_tool_registration_service.py

@@ -101,10 +101,12 @@ async def add_tool_servers_to_agent(
         # Convert MCP server configs to MCPServerInfo objects
         mcp_servers_info = []
         for server_config in mcp_server_configs:
+            # Use mcp_server_name if available (not None or empty), otherwise fall back to mcp_server_unique_name
+            server_name = server_config.mcp_server_name or server_config.mcp_server_unique_name
             # Use the URL from config (always populated by the configuration service)
             server_url = server_config.url
             server_info = MCPServerInfo(
-                name=server_config.mcp_server_name,
+                name=server_name,
                 url=server_url,
             )
             mcp_servers_info.append(server_info)