feat(species): auto-classify variety species from its label

Infer the catalog species a free-text variety label names ("Maiz de la
abuela" -> Zea mays) and prefill the category from the species family.

- Pure, testable matcher (domain/species_autoclassify.dart): whole-word,
  accent/case-insensitive, Unicode-aware (any script), longest-name-wins,
  ambiguous names left unclassified, light plural fold.
- Quick-add and draft naming auto-link the species when the field is empty
  (non-destructive; an explicit category is kept).
- Edit sheet offers a one-tap suggestion from the typed name.

Tests: matcher unit, repository integration, SpeciesRepository.classifyLabel,
and an edit-sheet widget test.

apps/app_seeds/test/domain/species_autoclassify_test.dart

@@ -0,0 +1,68 @@
+import 'package:flutter_test/flutter_test.dart';
+import 'package:tane/domain/species_autoclassify.dart';
+
+/// A small catalog spanning the tricky cases: accents, multi-word names, a
+/// name shared across two species, and substrings that must NOT fire.
+const _names = [
+  SpeciesNameEntry(speciesId: 'zea', name: 'Maíz'),
+  SpeciesNameEntry(speciesId: 'zea', name: 'Maize'),
+  SpeciesNameEntry(speciesId: 'zea', name: 'Zea mays'),
+  SpeciesNameEntry(speciesId: 'tomato', name: 'Tomate'),
+  SpeciesNameEntry(speciesId: 'tomato', name: 'Tomato'),
+  SpeciesNameEntry(speciesId: 'bean', name: 'Common bean'),
+  SpeciesNameEntry(speciesId: 'faba', name: 'Broad bean'),
+  SpeciesNameEntry(speciesId: 'faba', name: 'Haba'),
+  SpeciesNameEntry(speciesId: 'pea', name: 'Pea'),
+  // "Calabaza" is deliberately shared → ambiguous, must stay unclassified.
+  SpeciesNameEntry(speciesId: 'pepo', name: 'Calabaza'),
+  SpeciesNameEntry(speciesId: 'maxima', name: 'Calabaza'),
+];
+
+void main() {
+  String? match(String label) => matchSpeciesInLabel(label, _names);
+
+  test('matches a common name embedded in a free-text label', () {
+    expect(match('Maíz de la abuela'), 'zea');
+    expect(match('Tomate cherry'), 'tomato');
+  });
+
+  test('is accent- and case-insensitive', () {
+    expect(match('MAIZ dulce'), 'zea'); // no accent, upper-case
+    expect(match('tomate rosa'), 'tomato');
+  });
+
+  test('matches the scientific name too', () {
+    expect(match('Zea mays landrace'), 'zea');
+  });
+
+  test('matches multi-word names as a contiguous phrase', () {
+    expect(match('Broad bean Aquadulce'), 'faba');
+    expect(match('Common bean from grandma'), 'bean');
+  });
+
+  test('prefers the longest (most specific) name', () {
+    // "bean" alone is not in the catalog, but the two-word names should win
+    // over any single-word coincidence.
+    expect(match('Broad bean'), 'faba');
+  });
+
+  test('folds a plural label word to a singular catalog name', () {
+    expect(match('Tomates de rama'), 'tomato');
+    expect(match('Habas de mi huerto'), 'faba');
+  });
+
+  test('does not fire on a substring that is not a whole word', () {
+    expect(match('Habanero picante'), isNull); // contains "haba" as substring
+    expect(match('Peach tree'), isNull); // contains "pea" as substring
+  });
+
+  test('returns null when a name is shared across species (ambiguous)', () {
+    expect(match('Calabaza de invierno'), isNull);
+  });
+
+  test('returns null when nothing matches', () {
+    expect(match('Girasol gigante'), isNull);
+    expect(match('   '), isNull);
+    expect(match(''), isNull);
+  });
+}