fix(inventory): merge draft + list watch into one subscription

InventoryCubit subscribed to watchInventory() and watchDrafts()
separately — two overlapping StreamGroups (both watching attachments)
re-emitted in a tight loop that starved the event loop and hung widget
tests' pumpAndSettle for 10+ minutes (home/inventory/quick-add all
timed out). Replace both with a single watchInventoryView() stream that
loads the catalogued list and the draft tray from one StreamGroup.

Full widget suite no longer hangs: 165 pass. One unrelated failure
remains in the v8 variety edit sheet (Save button pushed off-screen by
new fields).

apps/app_seeds/lib/data/variety_repository.dart

@@ -365,6 +365,27 @@ class VarietyRepository {
     return triggers.asyncMap((_) => _loadInventory());
   }
 
+  /// The whole inventory screen in one reactive subscription: the catalogued
+  /// list and the draft tray, from a single [StreamGroup]. The cubit MUST use
+  /// this rather than subscribing to [watchInventory] and [watchDrafts]
+  /// separately — two overlapping StreamGroups (both watching `attachments`)
+  /// re-emit in a tight loop that starves the event loop and hangs widget
+  /// tests' `pumpAndSettle`.
+  Stream<({List<VarietyListItem> items, List<VarietyListItem> drafts})>
+  watchInventoryView() {
+    final triggers = StreamGroup.merge<void>([
+      (_db.select(
+        _db.varieties,
+      )..where((v) => v.isDeleted.equals(false))).watch().map((_) {}),
+      _db.select(_db.attachments).watch().map((_) {}),
+      _db.select(_db.species).watch().map((_) {}),
+      _db.select(_db.lots).watch().map((_) {}),
+    ]);
+    return triggers.asyncMap(
+      (_) async => (items: await _loadInventory(), drafts: await _loadDrafts()),
+    );
+  }
+
   Future<List<VarietyListItem>> _loadInventory() async {
     final rows =
         await (_db.select(_db.varieties)

apps/app_seeds/lib/state/inventory_cubit.dart

@@ -121,17 +121,20 @@ class InventoryState extends Equatable {
 /// automatically after a quick-add — no manual refresh.
 class InventoryCubit extends Cubit<InventoryState> {
   InventoryCubit(this._repo) : super(const InventoryState()) {
-    _sub = _repo.watchInventory().listen(
+    // One combined subscription (list + draft tray). Two separate StreamGroups
-      (items) => emit(state.copyWith(items: items, loading: false)),
+    // here re-emit in a loop that hangs widget tests — see watchInventoryView.
-    );
+    _sub = _repo.watchInventoryView().listen(
-    _draftsSub = _repo.watchDrafts().listen(
+      (view) => emit(
-      (drafts) => emit(state.copyWith(drafts: drafts)),
+        state.copyWith(items: view.items, drafts: view.drafts, loading: false),
+      ),
     );
   }
 
   final VarietyRepository _repo;
-  late final StreamSubscription<List<VarietyListItem>> _sub;
+  late final StreamSubscription<
-  late final StreamSubscription<List<VarietyListItem>> _draftsSub;
+    ({List<VarietyListItem> items, List<VarietyListItem> drafts})
+  >
+  _sub;
 
   void search(String query) => emit(state.copyWith(query: query));
 
@@ -171,7 +174,6 @@ class InventoryCubit extends Cubit<InventoryState> {
   @override
   Future<void> close() async {
     await _sub.cancel();
-    await _draftsSub.cancel();
     return super.close();
   }
 }