feat(themes): 新增推荐主题与用户主题批量删除功能

- 新增 getRecommendedThemes：按真实下载量降序返回8个未购买主题
- 新增 batchDeleteUserThemes：支持用户批量逻辑删除已购主题
- 补充接口注释与 Swagger 文档，开放 /themes/recommended 免鉴权路径

src/main/java/com/yolo/keyborad/controller/ThemesController.java

@@ -83,4 +83,12 @@ public class ThemesController {
         return ResultUtils.success(result);
     }
 
+    @GetMapping("/recommended")
+    @Operation(summary = "推荐主题列表", description = "按真实下载数量降序返回推荐主题")
+    public BaseResponse<List<KeyboardThemesRespVO>> getRecommendedThemes() {
+        Long userId = StpUtil.getLoginIdAsLong();
+        List<KeyboardThemesRespVO> result = themesService.getRecommendedThemes(userId);
+        return ResultUtils.success(result);
+    }
+
 }

src/main/java/com/yolo/keyborad/controller/UserThemesController.java

@@ -0,0 +1,34 @@
+package com.yolo.keyborad.controller;
+
+import cn.dev33.satoken.stp.StpUtil;
+import com.yolo.keyborad.common.BaseResponse;
+import com.yolo.keyborad.common.ResultUtils;
+import com.yolo.keyborad.model.dto.usertheme.BatchDeleteUserThemesReq;
+import com.yolo.keyborad.service.KeyboardUserThemesService;
+import io.swagger.v3.oas.annotations.Operation;
+import io.swagger.v3.oas.annotations.tags.Tag;
+import jakarta.annotation.Resource;
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.web.bind.annotation.*;
+
+/*
+ * @author: ziin
+ * @date: 2025/12/11
+ */
+@RestController
+@Slf4j
+@RequestMapping("/user-themes")
+@Tag(name = "用户主题")
+public class UserThemesController {
+
+    @Resource
+    private KeyboardUserThemesService userThemesService;
+
+    @PostMapping("/batch-delete")
+    @Operation(summary = "批量删除用户主题", description = "批量逻辑删除用户主题")
+    public BaseResponse<Boolean> batchDeleteUserThemes(@RequestBody BatchDeleteUserThemesReq req) {
+        Long userId = StpUtil.getLoginIdAsLong();
+        userThemesService.batchDeleteUserThemes(userId, req.getThemeIds());
+        return ResultUtils.success(true);
+    }
+}