feat(ai-chat): 新增豆包API + AI模型配置项支持动态切换

- 后端新增豆包（火山引擎Ark）API集成：DoubaoController、ToolDoubaoServiceImpl，
  使用OkHttp3 SSE流式对话，兼容OpenAI Chat Completions格式
- 新增DoubaoConfig配置类，读取doubao.api.*配置
- 在eb_system_config表新增ai_chat_model配置项，支持doubao/coze/gemini三种模型切换
- 新增GET /api/front/doubao/ai-model-config接口供前端读取当前模型配置
- 前端ai-nutritionist.vue的sendToAI按系统配置分发到_sendViaDoubao/_sendViaCoze/_sendViaGemini
- 前端models-api.js新增doubaoChatStream/doubaoChat/getAiModelConfig函数
- 附带豆包API测试脚本和数据库初始化SQL

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

msh_crmeb_22/crmeb-common/src/main/java/com/zbkj/common/config/DoubaoConfig.java

@@ -0,0 +1,43 @@
+package com.zbkj.common.config;
+
+import lombok.Data;
+import org.springframework.boot.context.properties.ConfigurationProperties;
+import org.springframework.context.annotation.Configuration;
+
+/**
+ * 豆包（火山引擎 Ark）API 配置类
+ * 使用 OpenAI 兼容的 Chat Completions 接口
+ * +----------------------------------------------------------------------
+ * | Author:ScottPan
+ * +----------------------------------------------------------------------
+ */
+@Data
+@Configuration
+@ConfigurationProperties(prefix = "doubao.api")
+public class DoubaoConfig {
+
+    /**
+     * API 基础 URL
+     */
+    private String baseUrl = "https://ark.cn-beijing.volces.com/api/v3";
+
+    /**
+     * API Key（火山引擎控制台获取）
+     */
+    private String apiKey;
+
+    /**
+     * 默认模型名称
+     */
+    private String model = "doubao-seed-2-0-pro-260215";
+
+    /**
+     * 连接超时时间（毫秒）
+     */
+    private Integer connectTimeout = 30000;
+
+    /**
+     * 读取超时时间（毫秒）
+     */
+    private Integer readTimeout = 120000;
+}

msh_crmeb_22/crmeb-common/src/main/java/com/zbkj/common/constants/SysConfigConstants.java

@@ -202,4 +202,7 @@ public class SysConfigConstants {
     /** 京东云存储端点 */
     public static final String CONFIG_JD_CLOUD_ENDPOINT = "jdEndpoint";
 
+    // ====== AI 模型配置 ======
+    /** AI 营养师对话模型选择: doubao / coze / gemini */
+    public static final String CONFIG_KEY_AI_CHAT_MODEL = "ai_chat_model";
 }

msh_crmeb_22/crmeb-common/src/main/java/com/zbkj/common/request/doubao/DoubaoChatRequest.java

@@ -0,0 +1,58 @@
+package com.zbkj.common.request.doubao;
+
+import io.swagger.annotations.ApiModel;
+import io.swagger.annotations.ApiModelProperty;
+import lombok.Data;
+import lombok.NoArgsConstructor;
+
+import javax.validation.Valid;
+import javax.validation.constraints.NotEmpty;
+import javax.validation.constraints.NotNull;
+import java.io.Serializable;
+import java.util.List;
+
+/**
+ * 豆包（火山引擎 Ark）Chat Completions 请求 DTO
+ * 兼容 OpenAI Chat Completions 格式
+ * +----------------------------------------------------------------------
+ * | Author:ScottPan
+ * +----------------------------------------------------------------------
+ */
+@Data
+@NoArgsConstructor
+@ApiModel(value = "DoubaoChatRequest", description = "豆包 Chat Completions 请求")
+public class DoubaoChatRequest implements Serializable {
+
+    private static final long serialVersionUID = 1L;
+
+    @Valid
+    @NotEmpty(message = "messages不能为空")
+    @ApiModelProperty(value = "消息列表", required = true)
+    private List<Message> messages;
+
+    @ApiModelProperty(value = "是否流式返回", example = "false")
+    private Boolean stream;
+
+    @ApiModelProperty(value = "模型名称（可选，不传则使用服务端默认配置）")
+    private String model;
+
+    @ApiModelProperty(value = "温度参数 (0-2)", example = "0.7")
+    private Double temperature;
+
+    @ApiModelProperty(value = "最大输出 token 数")
+    private Integer maxTokens;
+
+    @Data
+    @NoArgsConstructor
+    @ApiModel(value = "Message", description = "单条消息")
+    public static class Message implements Serializable {
+        private static final long serialVersionUID = 1L;
+
+        @ApiModelProperty(value = "角色: system, user, assistant")
+        private String role;
+
+        @NotNull(message = "content不能为空")
+        @ApiModelProperty(value = "内容：字符串或多模态数组", required = true)
+        private Object content;
+    }
+}