refactor: add service layer architecture with Pydantic validation

- Add services layer (PartyService, ScheduleService, ProductService, ServiceCenterService)
- Add ServiceProvider for dependency injection
- Add Pydantic input validation on all MCP tools
- Add thread-safety to TrytonSettings with double-checked locking
- Update tests to mock ServiceProvider instead of direct client calls
- Add pydantic dependency

tests/test_customer.py

@@ -1,48 +1,61 @@
 import pytest
-import sys
-from pathlib import Path
+import pytest_asyncio
+from unittest.mock import MagicMock, patch
 import json
 
-from tryton_mcp.server import create_customer
-
+import sys
+from pathlib import Path
 
 sys.path.insert(0, str(Path(__file__).parent / "src"))
 
 
+@pytest.fixture
+def mock_client():
+    return MagicMock()
+
+
+@pytest.fixture
+def mock_service_provider(mock_client):
+    provider_mock = MagicMock()
+    mock_response = MagicMock()
+    mock_response.is_error = False
+    mock_response.data = []
+
+    provider_mock.party.find_by_identifier.return_value = mock_response
+    provider_mock.party.create.return_value = mock_response
+
+    return provider_mock
+
+
+@pytest.fixture
+def server_with_mocks(mock_service_provider):
+    with patch("tryton_mcp.server._service_provider", mock_service_provider):
+        yield mock_service_provider
+
+
 @pytest.mark.asyncio
 class TestParty:
+    async def test_create_new_customer(self, server_with_mocks):
+        from tryton_mcp.server import create_customer
 
-    async def test_create_new_customer(self, mcp_client, mock_settings):
-        mock_client = mock_settings.get_client.return_value
-        mock_client.call.return_value = [1]
+        server_with_mocks.party.create.return_value.data = [1]
 
-        result = await mcp_client.call_tool(
-            "create_customer",
-            {
-                "name": "Alejandro Zapata",
-                "identifiers": [["create", [{"type": "mobile", "code": "310659595"}]]],
-            },
+        result = create_customer(
+            name="Alejandro Zapata",
+            identifiers=[["create", [{"type": "mobile", "code": "310659595"}]]],
         )
 
-        assert result.content is not None
-        assert len(result.content) == 1
-        assert result.content[0].text == "[1]"
+        assert result == [1]
 
-    async def test_find_customer(self, mcp_client, mock_settings):
+    async def test_find_customer(self, server_with_mocks):
+        from tryton_mcp.server import find_customer_by_identifier
 
         expected_return = [
-            {'id': 19, 'party': 44, 'party.': {'name': 'Alejandro Zapata', 'id': 44}}
+            {"id": 19, "party": 44, "party.": {"name": "Alejandro Zapata", "id": 44}}
         ]
 
-        mock_client = mock_settings.get_client.return_value
-        mock_client.call.return_value = expected_return
-        
-        result = await mcp_client.call_tool(
-            "find_customer_by_identifier",
-            {
-                "identifier": "310659595"
-            })
-        
-        assert result.content is not None
-        assert len(result.content) == 1
-        assert json.loads(result.content[0].text) == expected_return
+        server_with_mocks.party.find_by_identifier.return_value.data = expected_return
+
+        result = find_customer_by_identifier("310659595")
+
+        assert result == expected_return