feat(plantare): reproduction-commitment data layer (schema v9)

The Plantare — a promise to reproduce seed and return some (data-model §2.7,
the seed-domain Pledge with return_kind=similar). NOT a sale. Local-first
v1: your honest ledger of commitments (from/to a person by name); the
bilateral signed cross-party form is a later social-layer phase.

- New Plantares table (SyncColumns): varietyId, direction (iReturn/owedToMe),
  counterparty, owedDescription, madeOn, dueBy, status (open/returned/
  forgiven), settledOn, note. schemaVersion 8 -> 9 with a guarded createTable
  migration; schema exported + migration-test helper regenerated.
- VarietyRepository: createPlantare / watchPlantares / watchPlantaresForVariety
  / setPlantareStatus / deletePlantare (soft-delete, CRDT-stamped).
- Included in backups + sync: InventorySnapshot + JSON codec (round-trips
  isDeleted) + exportInventory/exportForSync/importInventory, so commitments
  survive restore and replicate LWW like every other row.

Tests: v1..v8 -> v9 migration + fresh v9; repo create/list/settle/reopen/
delete; and a backup round-trip preserving a commitment. 13 green.

UI (detail section + Plantares screen) follows.

apps/app_seeds/test/db/migration_test.dart

@@ -11,68 +11,20 @@ void main() {
     verifier = SchemaVerifier(GeneratedHelper());
   });
 
-  test('freshly created database matches the exported schema v8', () async {
-    final schema = await verifier.schemaAt(8);
+  test('freshly created database matches the exported schema v9', () async {
+    final schema = await verifier.schemaAt(9);
     final db = AppDatabase(schema.newConnection());
-    await verifier.migrateAndValidate(db, 8);
+    await verifier.migrateAndValidate(db, 9);
     await db.close();
   });
 
-  test('upgrades v1 → v8 (Lot.type, harvestMonth, presentation, '
-      'Attachment.sortOrder, Variety.isDraft/isOrganic, Species.viabilityYears, '
-      'v8 provenance/calendar/abundance/condition-checks) and matches the fresh '
-      'schema', () async {
-    final connection = await verifier.startAt(1);
-    final db = AppDatabase(connection);
-    await verifier.migrateAndValidate(db, 8);
-    await db.close();
-  });
-
-  test('upgrades v2 → v8 and matches the fresh schema', () async {
-    final connection = await verifier.startAt(2);
-    final db = AppDatabase(connection);
-    await verifier.migrateAndValidate(db, 8);
-    await db.close();
-  });
-
-  test('upgrades v3 → v8 and matches the fresh schema', () async {
-    final connection = await verifier.startAt(3);
-    final db = AppDatabase(connection);
-    await verifier.migrateAndValidate(db, 8);
-    await db.close();
-  });
-
-  test('upgrades v4 → v8 and matches the fresh schema', () async {
-    final connection = await verifier.startAt(4);
-    final db = AppDatabase(connection);
-    await verifier.migrateAndValidate(db, 8);
-    await db.close();
-  });
-
-  test(
-    'upgrades v5 → v8 (adds Variety.isDraft) and matches the fresh schema',
-    () async {
-      final connection = await verifier.startAt(5);
+  // Every historical version upgrades cleanly to the current schema (v9).
+  for (var from = 1; from <= 8; from++) {
+    test('upgrades v$from → v9 and matches the fresh schema', () async {
+      final connection = await verifier.startAt(from);
       final db = AppDatabase(connection);
-      await verifier.migrateAndValidate(db, 8);
+      await verifier.migrateAndValidate(db, 9);
       await db.close();
-    },
-  );
-
-  test('upgrades v6 → v8 (adds Variety.isOrganic, Species.viabilityYears) and '
-      'matches the fresh schema', () async {
-    final connection = await verifier.startAt(6);
-    final db = AppDatabase(connection);
-    await verifier.migrateAndValidate(db, 8);
-    await db.close();
-  });
-
-  test('upgrades v7 → v8 (adds Variety.needsReproduction + crop calendar, '
-      'Lot.origin/abundance/preservationFormat, ConditionChecks) and matches '
-      'the fresh schema', () async {
-    final connection = await verifier.startAt(7);
-    final db = AppDatabase(connection);
-    await verifier.migrateAndValidate(db, 8);
-    await db.close();
-  });
+    });
+  }
 }

apps/app_seeds/test/db/schema/schema.dart

@@ -12,6 +12,7 @@ import 'schema_v5.dart' as v5;
 import 'schema_v6.dart' as v6;
 import 'schema_v7.dart' as v7;
 import 'schema_v8.dart' as v8;
+import 'schema_v9.dart' as v9;
 
 class GeneratedHelper implements SchemaInstantiationHelper {
   @override
@@ -33,10 +34,12 @@ class GeneratedHelper implements SchemaInstantiationHelper {
         return v7.DatabaseAtV7(db);
       case 8:
         return v8.DatabaseAtV8(db);
+      case 9:
+        return v9.DatabaseAtV9(db);
       default:
         throw MissingSchemaException(version, versions);
     }
   }
 
-  static const versions = const [1, 2, 3, 4, 5, 6, 7, 8];
+  static const versions = const [1, 2, 3, 4, 5, 6, 7, 8, 9];
 }