refactor(common): 简化 ErrorCode 枚举并升级模型配置

- 使用 Lombok @Getter 移除手写 getter，精简 5 行代码
- 将 embedding 模型从 0.6B 升级为 8B 提升效果
- 切换 OpenRouter 网关地址到 Cloudflare AI Gateway 加速访问

src/main/java/com/yolo/keyborad/common/ErrorCode.java

@@ -1,10 +1,13 @@
 package com.yolo.keyborad.common;
 
+import lombok.Getter;
+
 /**
  * 错误码
  *
  * @author yupi
  */
+@Getter
 public enum ErrorCode {
 
     SUCCESS(0, "ok"),
@@ -31,12 +34,4 @@ public enum ErrorCode {
         this.message = message;
     }
 
-    public int getCode() {
-        return code;
-    }
-
-    public String getMessage() {
-        return message;
-    }
-
 }

src/main/java/com/yolo/keyborad/config/LLMConfig.java

@@ -53,7 +53,7 @@ public class LLMConfig {
                 this.openAiApi(),
                 MetadataMode.EMBED,
                 OpenAiEmbeddingOptions.builder()
-                        .model("qwen/qwen3-embedding-0.6b")
+                        .model("qwen/qwen3-embedding-8b")
                         .dimensions(2048)
                         .user("user-6")
                         .build(),

src/main/resources/application.yml

@@ -2,7 +2,7 @@ spring:
   ai:
     openai:
       api-key: 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
-      base-url: https://openrouter.ai/api/
+      base-url: https://gateway.ai.cloudflare.com/v1/b632a61caa85401f63c9b32eef3a74c8/aigetway/openrouter
       chat:
         options:
           model: google/gemini-2.5-flash-lite