feat(script-favorite): add ScriptFavoriteService interface

- toggleFavorite: toggle favorite status for a script
- getFavoritePage: paginated list of user's favorite scripts
- getFavoritedScriptIds: batch check which scripts are favorited
- isFavorited: check single script favorite status
- getFavoriteCount: count user's total favorites

server/src/main/java/com/emotion/service/ScriptFavoriteService.java

@@ -0,0 +1,28 @@
+package com.emotion.service;
+
+import com.baomidou.mybatisplus.extension.service.IService;
+import com.emotion.common.PageResult;
+import com.emotion.dto.response.EpicScriptResponse;
+import com.emotion.dto.response.ScriptFavoriteResponse;
+import com.emotion.entity.ScriptFavorite;
+
+import java.util.Set;
+
+/**
+ * 剧本收藏服务接口
+ *
+ * @author huazhongmin
+ * @date 2026-07-19
+ */
+public interface ScriptFavoriteService extends IService<ScriptFavorite> {
+
+    ScriptFavoriteResponse toggleFavorite(String scriptId);
+
+    PageResult<EpicScriptResponse> getFavoritePage(long current, long size);
+
+    Set<String> getFavoritedScriptIds(Set<String> scriptIds);
+
+    boolean isFavorited(String scriptId);
+
+    long getFavoriteCount();
+}