fix: AI Agent 对话增加 /mcp/agent/chat，避免 OMS 反代漏配 /ai

Co-authored-by: Cursor <cursoragent@cursor.com>

src/Oms.Application/Services/Mcp/McpToolService.cs

@@ -101,7 +101,8 @@ public class McpToolService : ApplicationService
     }
 
     /// <summary>AI Agent 对话（可自动调用已启用 MCP 工具；带防滥用限流）</summary>
-    [HttpPost("/ai/agent/chat")]
+    [HttpPost("/mcp/agent/chat")]
+    [HttpPost("/ai/agent/chat")] // 兼容旧路径；生产 OMS 反代请走 /mcp/*
     public async Task<AiAgentChatOutput> AgentChatAsync(AiAgentChatInput input)
     {
         var customerId = await OmsSessionHelper.ResolveXhsCustomerIdAsync(CustomerRepository, CurrentUser);