T4: Repository pattern — ModelRepository, JsonFileRepository, ExcelRepository

- application/repositories/model_repository.py: ModelRepository Protocol
  with load(path) and save(model, path)
- infrastructure/repositories/json_file_repository.py: JsonFileRepository
  (вынесен из FinancialModel.save/load)
- infrastructure/repositories/excel_repository.py: ExcelRepository
  (бывший ExcelSync, переименован)
- FinancialModel.save/load удалены — теперь только данные
- infrastructure/sync/ удалён (ExcelSync перенесён в repositories/)
- infrastructure/cli/main.py и config.py используют JsonFileRepository +
  ExcelRepository через локальные singletons
- test_excel_sync.py переименован в test для ExcelRepository
- Новый test_repositories.py: 5 тестов для JsonFileRepository + протокол
- test_model.py: использован JsonFileRepository

Tests: 68/68 pass (было 63 + 5 новых).

tests/test_excel_sync.py

@@ -1,22 +1,22 @@
 from pathlib import Path
 
 from domain import FinancialModel
-from infrastructure.sync.excel_sync import ExcelSync, SyncError
+from infrastructure.repositories import ExcelRepository, ExcelRepositoryError
 
 
-class TestExcelSync:
+class TestExcelRepository:
     def test_export_creates_file(self, sample_model, tmp_path: Path):
-        sync = ExcelSync()
+        repo = ExcelRepository()
         p = tmp_path / "test.xlsx"
-        sync.export_model(sample_model, p)
+        repo.save(sample_model, p)
         assert p.exists()
 
     def test_export_import_roundtrip(self, sample_model, tmp_path: Path):
-        sync = ExcelSync()
+        repo = ExcelRepository()
         p = tmp_path / "roundtrip.xlsx"
-        sync.export_model(sample_model, p)
+        repo.save(sample_model, p)
 
-        loaded = sync.import_model(p)
+        loaded = repo.load(p)
         assert len(loaded.accounts) == len(sample_model.accounts)
         assert len(loaded.transactions) == len(sample_model.transactions)
         assert len(loaded.recurring) == len(sample_model.recurring)
@@ -25,25 +25,25 @@ class TestExcelSync:
         assert len(loaded.exchange_rates) == len(sample_model.exchange_rates)
 
     def test_roundtrip_preserves_base_currency(self, tmp_path: Path):
-        sync = ExcelSync()
+        repo = ExcelRepository()
         model = FinancialModel(base_currency="EUR")
         p = tmp_path / "eur_model.xlsx"
-        sync.export_model(model, p)
+        repo.save(model, p)
 
-        loaded = sync.import_model(p)
+        loaded = repo.load(p)
         assert loaded.base_currency == "EUR"
 
     def test_import_missing_file(self):
-        sync = ExcelSync()
+        repo = ExcelRepository()
         try:
-            sync.import_model("nonexistent.xlsx")
-            assert False, "Expected SyncError"
-        except SyncError:
+            repo.load("nonexistent.xlsx")
+            assert False, "Expected ExcelRepositoryError"
+        except ExcelRepositoryError:
             pass
 
     def test_export_empty_model(self, tmp_path: Path):
-        sync = ExcelSync()
+        repo = ExcelRepository()
         model = FinancialModel()
         p = tmp_path / "empty.xlsx"
-        sync.export_model(model, p)
+        repo.save(model, p)
         assert p.exists()