fix: Resolve Windows path handling and editor command test issues

aider/editor.py

@@ -88,13 +88,13 @@ def get_environment_editor(default=None):
 
 def discover_editor(editor_override=None):
     """
-    Discovers and returns the appropriate editor command as a list of arguments.
+    Discovers and returns the appropriate editor command.
 
     Handles cases where the editor command includes arguments, including quoted arguments
     with spaces (e.g. 'vim -c "set noswapfile"').
 
-    :return: A list of command parts ready for subprocess execution
+    :return: The editor command as a string
-    :rtype: list[str]
+    :rtype: str
     """
     system = platform.system()
     if system == "Windows":

tests/basic/test_editor.py

@@ -109,7 +109,7 @@ with open("{log_path}", "w") as f:
             called_args = f.read().strip()
 
         # Verify the editor was called with a .md file
-        assert called_args.endswith(".md"), called_args
+        assert called_args.endswith(".md"), f"Called args: {called_args!r}"
 
     finally:
         # Clean up