feat(presentation): add type colors helper

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

lib/presentation/theme/type_colors.dart

@@ -0,0 +1,35 @@
+import 'package:flutter/material.dart';
+import '../../domain/entities/pokemon.dart';
+
+/// Couleur d'affichage associée à un type de Pokémon.
+Color typeToColor(PokemonType type) {
+  final Map<PokemonType, Color> map = {
+    PokemonType.normal: Colors.white,
+    PokemonType.fire: Colors.red,
+    PokemonType.water: Colors.blue,
+    PokemonType.electric: Colors.yellow,
+    PokemonType.grass: Colors.green,
+    PokemonType.ice: Colors.cyan,
+    PokemonType.fighting: Colors.orange,
+    PokemonType.poison: Colors.purple,
+    PokemonType.ground: Colors.brown,
+    PokemonType.flying: Colors.indigo,
+    PokemonType.psychic: Colors.pink,
+    PokemonType.bug: Colors.lightGreen,
+    PokemonType.rock: Colors.grey,
+    PokemonType.ghost: Colors.indigo,
+    PokemonType.dragon: Colors.indigo,
+    PokemonType.dark: Colors.black45,
+    PokemonType.steel: Colors.grey.shade600,
+    PokemonType.fairy: Colors.pinkAccent,
+    PokemonType.unknown: Colors.transparent,
+    PokemonType.shadow: Colors.transparent,
+  };
+  return map[type] ?? Colors.transparent;
+}
+
+/// Nom du type avec une majuscule initiale.
+String formatedTypeName(PokemonType type) {
+  final typeName = type.name;
+  return typeName[0].toUpperCase() + typeName.substring(1);
+}