chore: remove legacy models/utils/api/database layers

Also moves stray lib/pages/quel-est-ce-pokemon.code-workspace to repo
root, and fixes two trivial test lint infos (curly_braces_in_flow_
control_structures, constant_identifier_names) to reach clean analyze.

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

test/data/pokemon_repository_test.dart

@@ -21,7 +21,7 @@ class FakeLocal implements PokemonLocalDataSource {
   Future<Pokemon?> getById(int id) async => store[id];
   @override
   Future<void> saveAll(List<Pokemon> pokemons) async {
-    for (final p in pokemons) store[p.id] = p;
+    for (final p in pokemons) { store[p.id] = p; }
   }
   @override
   Future<void> update(Pokemon pokemon) async => store[pokemon.id] = pokemon;