Move "system" command to the root

platformio/maintenance.py

@@ -23,13 +23,13 @@ from platformio import __version__, app, exception, fs, telemetry
 from platformio.cache import cleanup_content_cache
 from platformio.cli import PlatformioCLI
 from platformio.commands.platform import platform_update as cmd_platform_update
-from platformio.commands.system.prune import calculate_unnecessary_system_data
 from platformio.commands.upgrade import get_latest_version
 from platformio.http import HTTPClientError, InternetIsOffline, ensure_internet_on
 from platformio.package.manager.core import update_core_packages
 from platformio.package.manager.tool import ToolPackageManager
 from platformio.package.meta import PackageSpec
 from platformio.package.version import pepver_to_semver
+from platformio.system.prune import calculate_unnecessary_system_data
 
 
 def on_platformio_start(ctx, force, caller):

platformio/system/cli.py

@@ -20,21 +20,21 @@ import click
 from tabulate import tabulate
 
 from platformio import __version__, compat, fs, proc, util
-from platformio.commands.system.completion import (
+from platformio.package.manager.library import LibraryPackageManager
+from platformio.package.manager.platform import PlatformPackageManager
+from platformio.package.manager.tool import ToolPackageManager
+from platformio.project.config import ProjectConfig
+from platformio.system.completion import (
     ShellType,
     get_completion_install_path,
     install_completion_code,
     uninstall_completion_code,
 )
-from platformio.commands.system.prune import (
+from platformio.system.prune import (
     prune_cached_data,
     prune_core_packages,
     prune_platform_packages,
 )
-from platformio.package.manager.library import LibraryPackageManager
-from platformio.package.manager.platform import PlatformPackageManager
-from platformio.package.manager.tool import ToolPackageManager
-from platformio.project.config import ProjectConfig
 
 
 @click.group("system", short_help="Miscellaneous system commands")