fix: implement environment-specific Python executable path resolution

Root cause: MCP server configurations were using hardcoded 'python' command
instead of environment-specific Python executable paths, causing servers
to run with wrong Python interpreter.

Changes:
- Update get_package_mcp_server_config() to use env_manager.get_current_python_executable()
- Fallback to 'python' if no environment-specific executable available
- Update test to mock get_current_python_executable() method properly
- Test now expects environment-specific path instead of generic 'python'

Resolves Issue 3: Incorrect Python Executable Path
Now generates proper paths like 'C:\Users\eliot\miniforge3\envs\hatch_modeling\python.exe'
instead of generic 'python' command.

Tested: All MCP CLI tests pass (100% success rate)

Author: LittleCoinCoin

hatch/cli_hatch.py

@@ -93,11 +93,17 @@ def get_package_mcp_server_config(env_manager: HatchEnvironmentManager, env_name
         if not hatch_mcp_entry_point:
             raise ValueError(f"Package '{package_name}' does not have a HatchMCP entry point")
 
+        # Get environment-specific Python executable
+        python_executable = env_manager.get_current_python_executable()
+        if not python_executable:
+            # Fallback to system Python if no environment-specific Python available
+            python_executable = "python"
+
         # Create server configuration
         server_path = str(package_path / hatch_mcp_entry_point)
         server_config = MCPServerConfig(
             name=package_name,
-            command="python",
+            command=python_executable,
             args=[server_path],
             env={}
         )

tests/test_mcp_cli_package_management.py

@@ -259,6 +259,8 @@ def test_get_package_mcp_server_config_success(self):
                 'source': {'path': '/path/to/package'}
             }
         ]
+        # Mock the Python executable method to return a proper string
+        mock_env_manager.get_current_python_executable.return_value = "/path/to/python"
 
         # Mock file system and metadata
         with patch('pathlib.Path.exists', return_value=True):
@@ -272,7 +274,7 @@ def test_get_package_mcp_server_config_success(self):
 
                     self.assertIsInstance(config, MCPServerConfig)
                     self.assertEqual(config.name, "test-package")
-                    self.assertEqual(config.command, "python")
+                    self.assertEqual(config.command, "/path/to/python")  # Now uses environment-specific Python
                     self.assertTrue(config.args[0].endswith("hatch_mcp_server.py"))
 
     @regression_test