restore proper error printing

Error represenation should be part of the error and we should not repeat
formatting here.
if we are in debug mode also print the stack trace

pkgs/clan-cli/clan_cli/__init__.py

@@ -24,7 +24,7 @@ from . import (
 from .clan_uri import FlakeId
 from .custom_logger import setup_logging
 from .dirs import get_clan_flake_toplevel_or_env
-from .errors import ClanCmdError, ClanError
+from .errors import ClanError
 from .facts import cli as facts
 from .flash import cli as flash_cli
 from .hyperlink import help_hyperlink
@@ -401,7 +401,7 @@ def main() -> None:
     if len(sys.argv) == 1:
         parser.print_help()
 
-    if getattr(args, "debug", False):
+    if debug := getattr(args, "debug", False):
         setup_logging(logging.DEBUG, root_log_name=__name__.split(".")[0])
         log.debug("Debug log activated")
     else:
@@ -413,20 +413,10 @@ def main() -> None:
     try:
         args.func(args)
     except ClanError as e:
-        if isinstance(e, ClanCmdError):
-            msg = ""
-            if e.cmd.msg:
-                msg += f"{e.cmd.msg}: "
-            msg += f"command exited with code {e.cmd.returncode}: {e.cmd.command}"
-            log.error(msg)  # noqa: TRY400
-            sys.exit(1)
-
-        if not e.msg:  # should not be empty, print stack trace
-            raise
-        msg = e.msg
-        if e.description:
-            msg += f": {e.description}"
-        log.error(msg)  # noqa: TRY400
+        if debug:
+            log.exception("Exited with error")
+        else:
+            log.error("%s", e)  # noqa: TRY400
             sys.exit(1)
     except KeyboardInterrupt:
         log.warning("Interrupted by user")