Update README and CLI documentation for tunnel functionality

- Enhanced README.md to clarify the `gpu-rent up` command, including default tunnel behavior and options for cloud-only operation.
- Updated cli.md to reflect changes in the `gpu-rent up` command, detailing the new `--no-tunnel` option and its implications.
- Revised decisions.md to explain the separation of `up` and `tunnel` commands, emphasizing the default tunnel opening after `up`.
- Improved doctor.py to provide clearer instructions regarding tunnel creation and cloud-only usage.
- Adjusted notify.py to reflect the updated command usage for accessing the SwarmUI.

src/gpu_rent/doctor.py

@@ -363,8 +363,8 @@ def dry_run_plan(checks: list[Check]) -> list[str]:
         f"idle-killer: {cfg.idle_minutes} мин пустой очереди, льгота {cfg.idle_grace_minutes} мин",
         "₽: в API нет — смотри панель; диск 24/7 даже после stop",
         f"туннель: localhost:{cfg.swarmui_local_port} -> VM :7801",
-        "gpu-rent up --yes создаст сеть/диски/compute и поставит SwarmUI (если doctor зелёный и квота GPU > 0)",
-        "после up: gpu-rent tunnel  (Ctrl+C не гасит GPU)",
+        "gpu-rent up --yes создаст GPU + SwarmUI и откроет туннель :17801 (Ctrl+C не гасит GPU)",
+        "только облако без туннеля: gpu-rent up --yes --no-tunnel",
     ]
     flavor = next((c.detail for c in checks if c.name == "flavor" and c.ok), None)
     if flavor: