feat(ui): align inventory + detail with mockups (seed icons, green theme)

Visual pass toward docs/mockups (06 inventory, 07 item):
- Bundle the seedks icon font (chars a–k → seed pictograms: jar, packet, spoon…)
  and a SeedGlyph/QuantityKindIcon helper.
- Green app bar + pale-green canvas theme (buildTaneTheme).
- Inventory list: rounded-square photo thumbnail or green initial avatar, bold
  title, scientific-name subtitle, trailing edit pencil, styled category
  headers, rounded search field, seed-glyph empty state.
- Quantity selectors (quick-add + add-lot) show the seed pictogram + word;
  detail lot lines use the kind's glyph.
- Detail header restyled to mockup 07: category link + scientific name on the
  left, photo on the right.

watchInventory now also returns the linked species' scientific name (subtitle).
37 app tests green; seedks font verified in the Linux asset bundle.

apps/app_seeds/lib/ui/variety_detail_screen.dart

@@ -6,6 +6,8 @@ import '../data/species_repository.dart';
 import '../data/variety_repository.dart';
 import '../i18n/strings.g.dart';
 import '../state/variety_detail_cubit.dart';
+import 'seed_glyph.dart';
+import 'theme.dart';
 import 'quantity_kind_l10n.dart';
 
 /// Read + edit view of a single variety: its photo, category, notes, other
@@ -72,33 +74,7 @@ class _DetailView extends StatelessWidget {
       body: ListView(
         padding: const EdgeInsets.all(16),
         children: [
-          if (detail.scientificName != null) ...[
-            Text(
-              detail.scientificName!,
-              style: Theme.of(context).textTheme.titleMedium?.copyWith(
-                fontStyle: FontStyle.italic,
-                color: Theme.of(context).colorScheme.onSurfaceVariant,
-              ),
-            ),
-            const SizedBox(height: 12),
-          ],
-          if (detail.photo != null)
-            ClipRRect(
-              borderRadius: BorderRadius.circular(12),
-              child: Image.memory(
-                detail.photo!,
-                height: 200,
-                width: double.infinity,
-                fit: BoxFit.cover,
-              ),
-            ),
-          if (detail.category != null) ...[
-            const SizedBox(height: 12),
-            Align(
-              alignment: Alignment.centerLeft,
-              child: Chip(label: Text(detail.category!)),
-            ),
-          ],
+          _DetailHeader(detail: detail),
           if (detail.vernacularNames.isNotEmpty) ...[
             const SizedBox(height: 16),
             _SectionTitle(t.detail.names),
@@ -134,7 +110,9 @@ class _DetailView extends StatelessWidget {
             for (final lot in detail.lots)
               ListTile(
                 contentPadding: EdgeInsets.zero,
-                leading: const Icon(Icons.inventory_2_outlined),
+                leading: lot.quantity == null
+                    ? const Icon(Icons.inventory_2_outlined)
+                    : QuantityKindIcon(lot.quantity!.kind, size: 28),
                 title: Text(_lotSubtitle(t, lot)),
                 subtitle: lot.storageLocation == null
                     ? null
@@ -548,6 +526,7 @@ Future<void> _showAddLotSheet(BuildContext context, VarietyDetailCubit cubit) {
               children: [
                 for (final kind in _addLotKinds)
                   ChoiceChip(
+                    avatar: QuantityKindIcon(kind, size: 18),
                     label: Text(quantityKindLabel(t, kind)),
                     selected: selectedKind == kind,
                     onSelected: (_) => setState(() => selectedKind = kind),
@@ -598,6 +577,61 @@ String? _nullIfBlank(String value) {
   return trimmed.isEmpty ? null : trimmed;
 }
 
+/// Mockup-07 header: category link + scientific name on the left, the photo on
+/// the right.
+class _DetailHeader extends StatelessWidget {
+  const _DetailHeader({required this.detail});
+
+  final VarietyDetail detail;
+
+  @override
+  Widget build(BuildContext context) {
+    final hasText = detail.category != null || detail.scientificName != null;
+    return Row(
+      crossAxisAlignment: CrossAxisAlignment.start,
+      children: [
+        Expanded(
+          child: Column(
+            crossAxisAlignment: CrossAxisAlignment.start,
+            children: [
+              if (detail.category != null)
+                Text(
+                  detail.category!,
+                  style: const TextStyle(
+                    color: seedLink,
+                    fontWeight: FontWeight.w600,
+                  ),
+                ),
+              if (detail.scientificName != null) ...[
+                const SizedBox(height: 2),
+                Text(
+                  detail.scientificName!,
+                  style: Theme.of(context).textTheme.bodyMedium?.copyWith(
+                    fontStyle: FontStyle.italic,
+                    color: Theme.of(context).colorScheme.onSurfaceVariant,
+                  ),
+                ),
+              ],
+            ],
+          ),
+        ),
+        if (detail.photo != null) ...[
+          if (hasText) const SizedBox(width: 12),
+          ClipRRect(
+            borderRadius: BorderRadius.circular(12),
+            child: Image.memory(
+              detail.photo!,
+              width: 140,
+              height: 140,
+              fit: BoxFit.cover,
+            ),
+          ),
+        ],
+      ],
+    );
+  }
+}
+
 class _SectionTitle extends StatelessWidget {
   const _SectionTitle(this.text);