Expand LotType from {seed, plant} to six append-only forms (seed,
seedling, plant, tree, bulb, cutting) and add an optional Presentation
attribute (pot/tray/plug/bareRoot/rootBall) kept separate from quantity
so 'how many' and 'in what packaging' never conflate.
Add attachments.sortOrder so the cover photo is the lowest-ordered one,
enabling reordering from the full-screen viewer. Expand QuantityKind
with the new plant-aware forms.
Migrations are additive (v1→v5 all covered by migration_test); enum
values are stored by name and appended only, keeping CRDT sync safe.