Fix remaining import errors: add ABC and abstractmethod imports to plugins.py, add unittest import to test_core.py

Author: sdirishguy

shellrosetta/plugins.py

@@ -3,8 +3,12 @@
 
 import os
 import sys
+import importlib.util
+from pathlib import Path
+from abc import ABC, abstractmethod
 from typing import Dict, List, Optional, Any, Callable
 import json
+
 class CommandPlugin(ABC):
     """Base class for command translation plugins"""
 

tests/test_core.py

@@ -1,7 +1,9 @@
 # tests/test_core.py
 
 
+import unittest
 from shellrosetta.core import lnx2ps, ps2lnx
+
 class TestShellRosettaCore(unittest.TestCase):
     def test_ls_translation(self):
         self.assertIn("Get-ChildItem", lnx2ps("ls"))