Update documentation to clarify GPU control commands

- Revised README, architecture, CLI, and other documentation to specify that both `Ctrl+C` and `Ctrl+D` now stop the GPU while preserving disk data, correcting previous inaccuracies.
- Enhanced access card and setup instructions to reflect the updated command behavior for better user understanding.
- Updated tests to ensure the new command behaviors are validated and documented correctly, improving overall clarity in GPU management.

tests/test_tunnel_watch.py

@@ -145,6 +145,7 @@ def _stub_tunnel(monkeypatch) -> None:
     monkeypatch.setattr("gpu_rent.tunnel.save_state", lambda s: None)
     monkeypatch.setattr("gpu_rent.access_card.print_access_card", lambda *a, **k: None)
     monkeypatch.setattr("gpu_rent.local_watchdog.watchdog_installed", lambda: False)
+    monkeypatch.setattr("gpu_rent.local_watchdog.clear_lease", lambda: None)
 
 
 def test_run_tunnel_ctrl_d_stops_gpu(monkeypatch):
@@ -163,7 +164,7 @@ def test_run_tunnel_ctrl_d_stops_gpu(monkeypatch):
     assert any("GPU остановлен" in x for x in logs)
 
 
-def test_run_tunnel_ctrl_c_keeps_gpu(monkeypatch):
+def test_run_tunnel_ctrl_c_stops_gpu(monkeypatch):
     _stub_tunnel(monkeypatch)
     logs: list[str] = []
     stopped: list[bool] = []
@@ -178,5 +179,6 @@ def test_run_tunnel_ctrl_c_keeps_gpu(monkeypatch):
         wait=boom,
         stop_gpu=lambda: stopped.append(True),
     )
-    assert stopped == []
-    assert any("GPU жив" in x for x in logs)
+    assert stopped == [True]
+    assert any("GPU остановлен" in x for x in logs)
+    assert not any("GPU жив" in x for x in logs)