Add support for gpu-rent.vars and enhance git update functionality

- Updated .gitignore to include gpu-rent.vars.
- Modified env.example to introduce the UPDATE_GIT variable for controlling git updates during execution.
- Implemented Import-GpuRentVars function in gpu-rent.ps1 to load environment variables from gpu-rent.vars.
- Enhanced gpu-rent.sh to support loading variables from gpu-rent.vars and added logic for handling default and extra arguments.
- Updated CLI documentation to reflect the new gpu-rent.vars file and its usage in configuration.
- Improved bootstrap and provisioning logic to conditionally perform git updates based on the new configuration.

src/gpu_rent/cli.py

@@ -301,6 +301,11 @@ def up(
         "--open/--no-open",
         help="После туннеля открыть браузер на 17801 (по умолчанию да)",
     ),
+    no_update: bool = typer.Option(
+        False,
+        "--no-update",
+        help="Не делать git pull SwarmUI и установленных extensions",
+    ),
 ) -> None:
     """Create/unshelve GPU, bootstrap SwarmUI, по умолчанию туннель на :17801."""
     try:
@@ -319,6 +324,7 @@ def up(
             flavor=flavor,
             yes=yes,
             adopt=adopt,
+            update=False if no_update else None,
             confirm=confirm,
             log=lambda m: console.print(m),
         )