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/pubspec.yaml

@@ -52,6 +52,9 @@ dependencies:
   image: ^4.3.0
   # Save/open dialogs for the inventory export/import (MIT license).
   file_picker: ^10.1.2
+  # Pure-Dart PDF generation (Apache-2.0) for the printable "what I share"
+  # catalog. No platform channels, so the whole flow is host-testable.
+  pdf: ^3.11.3
   path: ^1.9.0
   path_provider: ^2.1.5
 
@@ -119,6 +122,12 @@ flutter:
     # Real packet photos for the on-device OCR validation integration test.
     # Remove before shipping if you don't want them in the bundle.
     - assets/ocr_fixtures/
+    # Embedded in generated PDFs (printable catalog). DejaVu covers Latin
+    # (extended), Cyrillic and Greek; like the OCR packs, PDF fonts are a
+    # per-locale resource — swap in wider coverage (Arabic, CJK) as locales
+    # land. Free license (Bitstream Vera / public domain additions).
+    - assets/fonts/DejaVuSans.ttf
+    - assets/fonts/DejaVuSans-Bold.ttf
   fonts:
     # Custom seed-themed icon glyphs (chars a–k). See docs/mockups/seedks-glyphs.png.
     - family: seedks