feat(inventory): local sharing — per-lot share terms, filter and printable catalog

The local half of the original Fase 2 (no network, no Offer entity yet):
- Lot sheet gains a 'do you share it?' choice (gift/swap first, sale last,
  never the default); declaring plenty of abundance reveals it with a nudge.
- Lot lines and list tiles badge shared batches; an 'I share' filter and
  a printable PDF catalog (paper bridge for fairs) round out the view.
- Catalog PDF embeds DejaVu (Latin-ext/Cyrillic/Greek); fonts are a
  per-locale resource like the OCR packs.

apps/app_seeds/lib/di/injector.dart

@@ -22,6 +22,7 @@ import '../services/ocr/label_text_extractor.dart';
 import '../services/ocr/ocr_language.dart';
 import '../services/ocr/tesseract_label_extractor.dart';
 import '../services/onboarding_store.dart';
+import '../services/share_catalog_service.dart';
 
 /// The app's service locator. Kept to the composition root — widgets get their
 /// repositories from here (or via BlocProvider), never by reaching into it deep
@@ -75,6 +76,9 @@ Future<void> configureDependencies() async {
     ..registerSingleton<OnboardingStore>(OnboardingStore(secretStore))
     ..registerSingleton<ExportImportService>(
       ExportImportService(repository: varietyRepository, files: fileService),
+    )
+    ..registerSingleton<ShareCatalogService>(
+      ShareCatalogService(files: fileService),
     );
 }