chore add core rust project files and diesel migrations

Track required workspace crates, scripts, and historical diesel migrations so the repository contains the complete runnable backend baseline.

Made-with: Cursor

htykc_models/migrations/2024-01-17-094242_init_tbls/down.sql

@@ -0,0 +1 @@
+-- This file should undo anything in `up.sql`

htykc_models/migrations/2024-01-17-094242_init_tbls/up.sql

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+-- Your SQL goes here
+
+create table kecheng
+(
+    id             varchar   not null
+        constraint kecheng_teacher_pk
+            primary key,
+    kecheng_name   varchar   not null,
+    kecheng_status varchar   not null,
+    kecheng_desc   varchar,
+    start_from     timestamp not null,
+    end_by         timestamp not null,
+    duration       integer,
+    root_id        varchar   not null
+        constraint kecheng_teacher_kecheng_teacher_id_fk
+            references kecheng,
+    kecheng_type   varchar,
+    parent_id      varchar   not null
+        constraint kecheng_kecheng_id_fk
+            references kecheng,
+    created_by     varchar,
+    created_at     timestamp
+);
+
+comment on column kecheng.duration is '课程时长（分钟）';
+
+comment on column kecheng.kecheng_type is '未来可能用前端的在线上课功能';
+
+comment on column kecheng.parent_id is '第一条数据的`parent_id`是自己。';
+
+create unique index kecheng_teacher_id_uindex
+    on kecheng (id);
+
+create table kecheng_repeat
+(
+    id                varchar not null
+        primary key,
+    kecheng_id        varchar not null
+        constraint kecheng_repeat_kecheng_id_fk
+            references kecheng,
+    start_from        timestamp,
+    end_by            timestamp,
+    repeat_start      timestamp,
+    repeat_cycle_days integer not null,
+    repeat_end        timestamp,
+    repeat_status     varchar not null
+);
+
+comment on column kecheng_repeat.start_from is '课程当天开始时间';
+
+comment on column kecheng_repeat.end_by is '课程的当天结束时间';
+
+comment on column kecheng_repeat.repeat_start is '不需要`repeat_end`了，因为同一组`kecheng_root_id`的数据按照`repeat_start`时间排列，后一个就是前一个的end时间。';
+
+comment on column kecheng_repeat.repeat_end is '重复课程的结束时间';
+
+comment on column kecheng_repeat.repeat_status is 'ON_GOING / STOPPED / PENDING / ... / STATUS优先级大于`repeat_end`';
+
+create table kecheng_users
+(
+    id             varchar not null
+        primary key,
+    user_id        varchar not null,
+    kecheng_id     varchar not null
+        constraint kecheng_users_kecheng_id_fk
+            references kecheng,
+    kecheng_status varchar not null,
+    user_type      varchar not null
+);
+
+comment on column kecheng_users.user_type is '老师，学生，助教，等等';
+
+