-- Replace shared buff quota with per-buff quotas.
-- Each buff type gets its own charge counter and period window.
-- buff_charges stores: {"rush": {"remaining": 5, "periodEnd": "2026-03-29T00:00:00Z"}, ...}

ALTER TABLE heroes ADD COLUMN IF NOT EXISTS buff_charges JSONB NOT NULL DEFAULT '{}';

COMMENT ON COLUMN heroes.buff_charges IS 'Per-buff-type free charge state: map of buff_type -> {remaining, periodEnd}. Replaces shared buff_free_charges_remaining.';