fix(history): preserve multiple balance updates on the same day

apps/api/prisma/migrations/202610010003_revision_sequence/migration.sql

@@ -0,0 +1,4 @@
+-- Preserve all amounts and dates; permit multiple independently ordered updates per day.
+ALTER TABLE `Revision` ADD COLUMN `sequence` INTEGER NOT NULL AUTO_INCREMENT, ADD UNIQUE INDEX `Revision_sequence_key` (`sequence`);
+CREATE INDEX `Revision_positionId_effectiveDate_idx` ON `Revision`(`positionId`, `effectiveDate`);
+DROP INDEX `Revision_positionId_effectiveDate_key` ON `Revision`;