refactor: 目标，任务，习惯都放一张表中

db/schema.sql

@@ -1,16 +1,14 @@
-drop table if exists `goals`;
+drop table if exists `goal`;
 
-CREATE TABLE if not exists `goals`
+CREATE TABLE if not exists `goal`
 (
-    id          INT auto_increment                               NOT NULL PRIMARY KEY,
+    id          INT unsigned auto_increment PRIMARY KEY,
     status      enum ('DOING', 'DONE', 'CANCEL') default 'DOING' not null,
     create_time DATETIME                                         NULL,
     update_time DATETIME                                         NULL,
+    type        enum('GOAL', 'TASK', 'HABIT')    default 'TASK'  NOT NULL ,
     name        varchar(100)                                     NOT NULL,
     tag         varchar(100)                                     NULL,
     detail      varchar(100)                                     NULL
 )
-    ENGINE = InnoDB
-    DEFAULT CHARSET = utf8mb4
-    COLLATE = utf8mb4_0900_ai_ci
-    COMMENT ='目标管理表';
+    COMMENT ='目标管理表';