refactor(workspace): replace colorama with Colors class in finders.py

Use the new semantic Colors class for error messages instead of raw
colorama.Fore.RED. This ensures consistent color handling across the
codebase and respects NO_COLOR/FORCE_COLOR environment variables.

Author: tony

src/tmuxp/workspace/finders.py

@@ -7,9 +7,8 @@
 import pathlib
 import typing as t
 
-from colorama import Fore
-
 from tmuxp._internal.private_path import PrivatePath
+from tmuxp.cli._colors import ColorMode, Colors
 from tmuxp.cli.utils import tmuxp_echo
 from tmuxp.workspace.constants import VALID_WORKSPACE_DIR_FILE_EXTENSIONS
 
@@ -362,11 +361,12 @@ def find_workspace_file(
             ]
 
             if len(candidates) > 1:
+                colors = Colors(ColorMode.AUTO)
                 tmuxp_echo(
-                    Fore.RED
-                    + "Multiple .tmuxp.{yml,yaml,json} workspace_files in "
-                    + dirname(workspace_file)
-                    + Fore.RESET,
+                    colors.error(
+                        "Multiple .tmuxp.{yml,yaml,json} workspace_files in "
+                        + dirname(workspace_file)
+                    ),
                 )
                 tmuxp_echo(
                     "This is undefined behavior, use only one. "