- Introduced `license_height_matrix` for mapping minimum license requirements to jump heights (ÖTO § 231).
- Added `horse_min_age_matrix` for defining minimum horse ages by discipline, height, or level (ÖTO § 103, FEI GR Art. 136).
- Populated both tables with ÖTO 2026 and FEI-compliant seed data.
- Updated Flyway V008 to remove incorrect `RD4` entry and annotated corrected enum references.
- Created Flyway V009 for introducing the new tables and their seeds.
- Aligned documentation, validation rules, and roadmaps for backend implementation handover.
Signed-off-by: Stefan Mogeritsch <stefan.mo.co@gmail.com>