feat(challenges): 新增挑战类型字段并重构进度上报逻辑

- 数据库新增 type 列区分 water/exercise/diet/mood/sleep/weight 六类挑战
- 进度上报由增量模式改为绝对值模式，字段 increment_value → reportedValue
- 服务层按 challenge.targetValue 判断当日是否完成，再按 minimumCheckInDays 统计总进度
- 相关 DTO 与模型同步更新，支持新类型返回

BREAKING CHANGE: 上报接口字段由 increment 改为 value，且为当日绝对值

sql-scripts/add-challenge-type-column.sql

@@ -0,0 +1,14 @@
+-- Add challenge type column to t_challenges table
+-- This migration adds the type column to support different challenge types
+
+ALTER TABLE t_challenges 
+ADD COLUMN type ENUM('water', 'exercise', 'diet', 'mood', 'sleep', 'weight') 
+NOT NULL DEFAULT 'water' 
+COMMENT '挑战类型' 
+AFTER cta_label;
+
+-- Create index on type column for better query performance
+CREATE INDEX idx_challenges_type ON t_challenges (type);
+
+-- Update existing challenges to have 'water' type if they don't have a type
+UPDATE t_challenges SET type = 'water' WHERE type IS NULL;