feat(分享): 新增故事分享反馈功能

实现故事分享的评论和浏览统计功能，包括：
1. 新增StoryShareFeedbackService接口及相关实现
2. 添加StoryShareComment、StoryShareMetric实体类
3. 创建story_share_comment和story_share_metric表
4. 在StoryDetailVo中增加shareConfigured和sharePublished字段
5. 扩展StoryShareConfigVo包含反馈统计数据
6. 新增公共API端点处理反馈请求
7. 实现模板样式选择功能

deploy/update_story_share_template.sql

@@ -0,0 +1,24 @@
+SET @story_share_table_exists = (
+  SELECT COUNT(*)
+  FROM information_schema.TABLES
+  WHERE TABLE_SCHEMA = DATABASE()
+    AND TABLE_NAME = 'story_share'
+);
+
+SET @story_share_template_exists = (
+  SELECT COUNT(*)
+  FROM information_schema.COLUMNS
+  WHERE TABLE_SCHEMA = DATABASE()
+    AND TABLE_NAME = 'story_share'
+    AND COLUMN_NAME = 'template_style'
+);
+
+SET @story_share_template_stmt = IF(
+  @story_share_table_exists = 1 AND @story_share_template_exists = 0,
+  "ALTER TABLE story_share ADD COLUMN template_style varchar(32) DEFAULT 'editorial' COMMENT 'Public template style' AFTER share_quote",
+  'SELECT 1'
+);
+
+PREPARE story_share_template_stmt FROM @story_share_template_stmt;
+EXECUTE story_share_template_stmt;
+DEALLOCATE PREPARE story_share_template_stmt;