-- Lets an adviser create a personal task for themselves, not just have
-- adviser_tasks auto-generated by AdviserTaskService off student streaks.
-- student_id becomes optional (a manual task doesn't have to be tied to a
-- student); title/description/due_date carry the free-form task content;
-- created_by records which adviser created it (system-generated rows leave
-- this NULL and are still attributable via students.adviser_id as before).
ALTER TABLE adviser_tasks
    MODIFY student_id INT NULL,
    ADD COLUMN title VARCHAR(150) NULL AFTER reason,
    ADD COLUMN description VARCHAR(1000) NULL AFTER title,
    ADD COLUMN due_date DATE NULL AFTER description,
    ADD COLUMN created_by BIGINT UNSIGNED NULL AFTER due_date;
