feat(ai): 切换默认模型并新增流式对话接口- 将默认模型从 deepseek-chat 切换为 deepseek-reasoner

- 新增 /ai/generateStream 接口支持流式对话输出
- 新增 /v1/ai/generateStream 接口支持 reasoning 内容流式输出
- 引入 commons-lang3 依赖用于字符串处理- 添加 Flux 支持实现异步流式响应
- 完善 DeepSeekAssistantMessage 处理逻辑，区分推理内容与最终回答

src/main/java/com/hanserwei/airobot/controller/DeepSeekChatController.java

@@ -1,11 +1,14 @@
 package com.hanserwei.airobot.controller;
 
 import jakarta.annotation.Resource;
+import org.springframework.ai.chat.messages.UserMessage;
+import org.springframework.ai.chat.prompt.Prompt;
 import org.springframework.ai.deepseek.DeepSeekChatModel;
 import org.springframework.web.bind.annotation.GetMapping;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RequestParam;
 import org.springframework.web.bind.annotation.RestController;
+import reactor.core.publisher.Flux;
 
 @RestController
 @RequestMapping("/ai")
@@ -25,4 +28,19 @@ public class DeepSeekChatController {
         return chatModel.call(message);
     }
 
+    /**
+     * 流式对话
+     * @param message 对话输入内容
+     * @return 对话结果
+     */
+    @GetMapping(value = "/generateStream", produces = "text/html;charset=utf-8")
+    public Flux<String> generateStream(@RequestParam(value = "message", defaultValue = "你是谁？") String message) {
+        // 构建提示词
+        Prompt prompt = new Prompt(new UserMessage(message));
+
+        // 流式输出
+        return chatModel.stream(prompt)
+                .mapNotNull(chatResponse -> chatResponse.getResult().getOutput().getText());
+    }
+
 }

src/main/java/com/hanserwei/airobot/controller/DeepSeekR1ChatController.java

@@ -0,0 +1,49 @@
+package com.hanserwei.airobot.controller;
+
+import jakarta.annotation.Resource;
+import org.apache.commons.lang3.StringUtils;
+import org.springframework.ai.chat.messages.UserMessage;
+import org.springframework.ai.chat.prompt.Prompt;
+import org.springframework.ai.deepseek.DeepSeekAssistantMessage;
+import org.springframework.ai.deepseek.DeepSeekChatModel;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RequestParam;
+import org.springframework.web.bind.annotation.RestController;
+import reactor.core.publisher.Flux;
+
+@RestController
+@RequestMapping("/v1/ai")
+public class DeepSeekR1ChatController {
+
+    @Resource
+    private DeepSeekChatModel chatModel;
+
+    /**
+     * 流式对话
+     * @param message 对话输入内容
+     * @return 对话结果
+     */
+    @GetMapping(value = "/generateStream", produces = "text/html;charset=utf-8")
+    public Flux<String> generateStream(@RequestParam(value = "message", defaultValue = "你是谁？") String message) {
+        // 构建提示词
+        Prompt prompt = new Prompt(new UserMessage(message));
+
+        // 流式输出
+        return chatModel.stream(prompt)
+                .mapNotNull(chatResponse -> {
+                    // 获取响应内容
+                    DeepSeekAssistantMessage deepSeekAssistantMessage = (DeepSeekAssistantMessage) chatResponse.getResult().getOutput();
+                    // 推理内容
+                    String reasoningContent = deepSeekAssistantMessage.getReasoningContent();
+                    // 推理结束后的正式回答
+                    String text = deepSeekAssistantMessage.getText();
+
+                    // 若推理内容有值，则响应推理内容，否则，说明推理结束了，响应正式回答
+                    return StringUtils.isNotBlank(reasoningContent) ? reasoningContent : text;
+                });
+
+
+
+    }
+}