feat: add eve chanting notif

migrations/0029_add_chant_incomplete_reminder.down.sql

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+ALTER TABLE users DROP COLUMN IF EXISTS last_chant_incomplete_reminder_on;

migrations/0029_add_chant_incomplete_reminder.up.sql

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+-- Evening "incomplete chanting" reminder.
+--
+-- last_chant_incomplete_reminder_on: the UTC date the 9 PM (local)
+-- "finish your rounds" reminder was last sent, so it goes out at most once
+-- per day. Distinct from the morning chant reminder so a devotee can get a
+-- gentle start-of-day nudge and, if their rounds are still unfinished, an
+-- end-of-day one.
+ALTER TABLE users ADD COLUMN IF NOT EXISTS last_chant_incomplete_reminder_on DATE;