fix: validate date format in create_schedule with clear error message

tests/test_customer.py

@@ -0,0 +1,48 @@
+import pytest
+import sys
+from pathlib import Path
+import json
+
+from tryton_mcp.server import create_customer
+
+
+sys.path.insert(0, str(Path(__file__).parent / "src"))
+
+
+@pytest.mark.asyncio
+class TestParty:
+
+    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]
+
+        result = await mcp_client.call_tool(
+            "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]"
+
+    async def test_find_customer(self, mcp_client, mock_settings):
+
+        expected_return = [
+            {'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