Covered Theme module with tests

- Extracted `ColorReplacementGenerator`;
- Extracted `ColorConverterImpl`;
- Added documentation to some classes;
- `hex_to_rgba` now supports shorthand hex colors (#fff).

scripts/utils/theme/theme_temp_manager.py

@@ -1,8 +1,6 @@
 import os
 import shutil
 
-from scripts.utils import copy_files
-
 
 class ThemeTempManager:
     """
@@ -10,18 +8,21 @@ class ThemeTempManager:
     """
     def __init__(self, temp_folder: str):
         self.temp_folder = temp_folder
+        os.makedirs(self.temp_folder, exist_ok=True)
 
     def copy_to_temp(self, content: str):
+        """
+        Copy a file or directory to the temporary folder.
+        If the content is a file, it will be copied directly.
+        If the content is a directory, all its contents will be copied to the temp folder.
+        """
         if os.path.isfile(content):
-            shutil.copy(content, self.temp_folder)
+            final_path = os.path.join(self.temp_folder, os.path.basename(content))
+            shutil.copy(content, final_path)
         else:
-            shutil.copytree(content, self.temp_folder)
+            shutil.copytree(content, self.temp_folder, dirs_exist_ok=True)
         return self
 
-    def prepare_files(self, sources_location: str):
-        """Prepare files in temp folder"""
-        copy_files(sources_location, self.temp_folder)
-
     def cleanup(self):
         """Remove temporary folders"""
         shutil.rmtree(f"{self.temp_folder}/.css/", ignore_errors=True)