refactor: define IMiniScoringService interface

Phase 1, Step 1.3.1: Extract scoring logic interface
- Define submitScore() method signature

Related to Phase 1 refactoring plan

src/main/java/org/springblade/modules/martial/service/IMiniScoringService.java

@@ -0,0 +1,18 @@
+package org.springblade.modules.martial.service;
+
+import org.springblade.core.tool.api.R;
+import org.springblade.modules.martial.pojo.dto.MiniScoreSubmitDTO;
+
+/**
+ * Mini App Scoring Service
+ * Phase 1, Step 1.3.1: Extract scoring logic from controller
+ */
+public interface IMiniScoringService {
+    
+    /**
+     * Submit score
+     * @param dto score submission data
+     * @return submission result
+     */
+    R<String> submitScore(MiniScoreSubmitDTO dto);
+}