Add study review planning and mock exam hub

drizzle/0002_add_study_hub.sql

@@ -0,0 +1,20 @@
+CREATE TABLE `study_days` (
+  `user_id` text NOT NULL,
+  `plan_date` text NOT NULL,
+  `durations` text NOT NULL DEFAULT '{}',
+  `weekly_review` text NOT NULL DEFAULT '',
+  `next_focus` text NOT NULL DEFAULT '',
+  `updated_at` text NOT NULL DEFAULT CURRENT_TIMESTAMP,
+  PRIMARY KEY(`user_id`, `plan_date`)
+);
+CREATE TABLE `mock_exams` (
+  `user_id` text NOT NULL,
+  `exam_date` text NOT NULL,
+  `listening` text NOT NULL DEFAULT '',
+  `reading` text NOT NULL DEFAULT '',
+  `writing` text NOT NULL DEFAULT '',
+  `translation` text NOT NULL DEFAULT '',
+  `note` text NOT NULL DEFAULT '',
+  `updated_at` text NOT NULL DEFAULT CURRENT_TIMESTAMP,
+  PRIMARY KEY(`user_id`, `exam_date`)
+);