feat(plantare): usable UI — commitments screen, add sheet, entry points

The reproduction-commitment (Plantare) UI, local-first and plain-spoken:
- A Plantares screen (drawer entry, /plantares) listing your commitments,
  grouped Open / Done, with a big 'mark returned', a menu (let it go / reopen
  / remove) and an empty-state that explains what a Plantare is.
- An add sheet (scrollable): a two-choice 'who reproduces & returns' (I return
  / owed to me), an optional 'with whom', an optional 'what comes back' in the
  grower's own words, and a note. No sale, no currency — a promise.
- Reachable from a seed too: an 'Add a commitment' action on the variety
  detail, pre-attached to that variety.
- i18n en/es/pt/ast (human words: 'Plantare' + a plain explanation).

Added the Plantares screen to the small-phone overflow guard (18 cases green).

apps/app_seeds/lib/app.dart

@@ -32,6 +32,7 @@ import 'ui/chat_screen.dart';
 import 'ui/home_screen.dart';
 import 'ui/intro_screen.dart';
 import 'ui/inventory_list_screen.dart';
+import 'ui/plantares_screen.dart';
 import 'ui/market_offer_detail_screen.dart';
 import 'ui/market_screen.dart';
 import 'ui/offline_banner.dart';
@@ -254,6 +255,11 @@ class TaneApp extends StatelessWidget {
             child: const InventoryListScreen(),
           ),
         ),
+        // Local reproduction commitments — inventory-adjacent, no network.
+        GoRoute(
+          path: '/plantares',
+          builder: (context, state) => const PlantaresScreen(),
+        ),
         GoRoute(
           path: '/variety/:id',
           builder: (context, state) => BlocProvider(