feat(shell): home menu + navigation drawer (mockups 02/03)

The app now opens on a main menu instead of straight into the list:
- HomeScreen (mockup 02): sprout logo over a faint seed-glyph watermark, with
  big "Your inventory" (→ /inventory) and "Open market" (Block 2, "coming soon")
  destinations.
- AppDrawer (mockup 03): Inventory is live; the social items (market, profile,
  chat, wishlist, following, settings) are shown disabled with a "coming soon"
  tag so the roadmap is visible. Drawer is available on home and inventory.
- Routing: / → home, /inventory → list, /variety/:id → detail.

Tests: home shows the menu + navigates; drawer opens + navigates. quick-add flow
updated to go home → inventory. 50 green; Linux runs.

apps/app_seeds/lib/i18n/strings.g.dart

@@ -4,9 +4,9 @@
 /// To regenerate, run: `dart run slang`
 ///
 /// Locales: 2
-/// Strings: 216 (108 per locale)
+/// Strings: 236 (118 per locale)
 ///
-/// Built on 2026-07-08 at 10:02 UTC
+/// Built on 2026-07-08 at 10:18 UTC
 
 // coverage:ignore-file
 // ignore_for_file: type=lint, unused_import