Adds schema migration v3 (recurrence_parent_id column + budget_recurrence_skipped
table). On every GET /api/v1/budget, the server checks all recurring originals
(is_recurring=1, no parent) and creates missing instances for the requested month
using the same day-of-month (clamped to the last day). Deleted instances are
recorded in budget_recurrence_skipped so they are not recreated on the next visit.
Generated instances are shown with a ↩ indicator in the transaction list.
Closes BL-05.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Ulas
82e5b2cd85