feat: 实现题目服务基础架构

- 创建题目服务模块 aioj-backend-question-service
- 实现 Question、TestCase、QuestionSubmit 实体类
- 实现 RESTful 风格的 Controller 接口
- 添加完善的 Swagger 注解和校验
- 配置 Nacos 服务发现和 Redis 缓存
- 实现分页查询和条件过滤功能

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

aioj-backend-question-service/src/main/resources/application.yml

@@ -0,0 +1,49 @@
+spring:
+  application:
+    name: aioj-question-service
+  profiles:
+    active: @env@
+server:
+  port: 18083
+  servlet:
+    context-path: /api
+  error:
+    include-stacktrace: never
+springdoc:
+  api-docs:
+    enabled: true
+    path: /v3/api-docs
+  default-flat-param-object: true
+  swagger-ui:
+    path: /swagger-ui.html
+    tags-sorter: alpha
+    operations-sorter: alpha
+  group-configs:
+    - group: 'default'
+      paths-to-match: '/api/**'
+      packages-to-scan: cn.meowrain.aioj.backend.questionservice.controller
+knife4j:
+  basic:
+    enable: true
+  setting:
+    language: zh_cn
+mybatis-plus:
+  configuration:
+    log-impl: org.apache.ibatis.logging.stdout.StdOutImpl
+    map-underscore-to-camel-case: true
+  mapper-locations: classpath*:/mapper/**/*.xml
+
+# JWT 配置（必须与 auth-service 保持一致）
+jwt:
+  enabled: true
+  secret: "12345678901234567890123456789012"  # 至少32字节
+  access-expire: 900000           # 15分钟
+  refresh-expire: 604800000       # 7天
+
+aioj:
+  log:
+    enabled: true
+    max-length: 20000
+logging:
+  file:
+    path: ./logs/${spring.application.name}