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/lib/data/species_repository.dart

@@ -2,6 +2,7 @@ import 'package:commons_core/commons_core.dart';
 import 'package:drift/drift.dart';
 
 import '../db/database.dart';
+import '../domain/species_autoclassify.dart';
 
 /// One entry from the bundled catalog, before it is stored.
 class SpeciesSeed {
@@ -249,6 +250,44 @@ class SpeciesRepository {
       .replaceAll('%', r'\%')
       .replaceAll('_', r'\_');
 
+  /// Auto-classification for the UI: infers the single species a free-text
+  /// variety [label] names (see [matchSpeciesInLabel]) and returns it as a
+  /// [SpeciesMatch] with a best common name for [languageCode]. Returns null
+  /// when the label names no known species or the match is ambiguous — so the
+  /// caller can offer it as a one-tap suggestion, never a silent guess.
+  Future<SpeciesMatch?> classifyLabel(
+    String label, {
+    String languageCode = 'en',
+  }) async {
+    final species = await (_db.select(
+      _db.species,
+    )..where((s) => s.isDeleted.equals(false))).get();
+    final commons = await (_db.select(
+      _db.speciesCommonNames,
+    )..where((n) => n.isDeleted.equals(false))).get();
+
+    final names = <SpeciesNameEntry>[
+      for (final s in species)
+        SpeciesNameEntry(speciesId: s.id, name: s.scientificName),
+      for (final c in commons)
+        SpeciesNameEntry(speciesId: c.speciesId, name: c.name),
+    ];
+    final id = matchSpeciesInLabel(label, names);
+    if (id == null) return null;
+
+    final match = species.firstWhere((s) => s.id == id);
+    final matchNames = [
+      for (final c in commons)
+        if (c.speciesId == id) (name: c.name, language: c.language),
+    ];
+    return SpeciesMatch(
+      id: match.id,
+      scientificName: match.scientificName,
+      family: match.family,
+      commonName: _bestName(matchNames, languageCode),
+    );
+  }
+
   String? _bestName(
     List<({String name, String? language})> names,
     String languageCode,