Update documentation and CLI behavior for GPU management

- Clarified the behavior of `Ctrl+C` and `Ctrl+D` in the README and other documentation, specifying that `Ctrl+C` only stops the tunnel while keeping the GPU active, and `Ctrl+D` stops the GPU while preserving disk data.
- Enhanced the CLI documentation to reflect these changes, ensuring users understand the implications of these commands during GPU operations.
- Improved the handling of data bindings and remounting logic in the codebase to prevent issues with empty model tabs in the UI.
- Added tests to validate the new command behaviors and ensure proper documentation alignment.

tests/test_tunnel_watch.py

@@ -1,4 +1,9 @@
-from gpu_rent.tunnel import decide_watch, tunnel_forwards
+import sys
+import time
+
+import pytest
+
+from gpu_rent.tunnel import decide_watch, poll_ctrl_d, run_tunnel, tunnel_forwards
 
 
 def test_decide_ok_active():
@@ -71,3 +76,107 @@ def test_resolve_llm_uses_cfg_only(monkeypatch):
         llm_runtime = "ollama"
 
     assert resolve_llm_runtime(Cfg2()) == "ollama"
+
+
+def test_poll_ctrl_d_skips_when_not_tty(monkeypatch):
+    monkeypatch.setattr("gpu_rent.tunnel.sys.stdin.isatty", lambda: False)
+    t0 = time.time()
+    assert poll_ctrl_d(0.02) is False
+    assert time.time() - t0 < 0.5
+
+
+def test_poll_ctrl_d_windows_eot(monkeypatch):
+    class Msvcrt:
+        def kbhit(self) -> bool:
+            return True
+
+        def getch(self) -> bytes:
+            return b"\x04"
+
+    monkeypatch.setattr("gpu_rent.tunnel.sys.stdin.isatty", lambda: True)
+    monkeypatch.setattr("gpu_rent.tunnel.os.name", "nt")
+    monkeypatch.setitem(sys.modules, "msvcrt", Msvcrt())
+    assert poll_ctrl_d(0.2) is True
+
+
+def test_poll_ctrl_d_windows_ctrl_c(monkeypatch):
+    class Msvcrt:
+        def kbhit(self) -> bool:
+            return True
+
+        def getch(self) -> bytes:
+            return b"\x03"
+
+    monkeypatch.setattr("gpu_rent.tunnel.sys.stdin.isatty", lambda: True)
+    monkeypatch.setattr("gpu_rent.tunnel.os.name", "nt")
+    monkeypatch.setitem(sys.modules, "msvcrt", Msvcrt())
+    with pytest.raises(KeyboardInterrupt):
+        poll_ctrl_d(0.2)
+
+
+class _Fwd:
+    is_active = True
+
+    def stop(self) -> None:
+        pass
+
+
+class _State:
+    notes: dict = {}
+    phase = ""
+    floating_ip = "1.2.3.4"
+
+
+class _Cfg:
+    ssh_user = "u"
+    ssh_private_key_path = "k"
+    swarmui_local_port = 17801
+    ollama_local_port = 17811
+    llm_runtime = "none"
+    enable_swarmui = True
+
+
+def _stub_tunnel(monkeypatch) -> None:
+    st = _State()
+    monkeypatch.setattr("gpu_rent.tunnel._ssh_tunnel_forwarder", lambda: object)
+    monkeypatch.setattr("gpu_rent.tunnel._start_forwarder", lambda *a, **k: _Fwd())
+    monkeypatch.setattr("gpu_rent.ready.verify_stack_local", lambda *a, **k: [])
+    monkeypatch.setattr("gpu_rent.tunnel.load_state", lambda: st)
+    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)
+
+
+def test_run_tunnel_ctrl_d_stops_gpu(monkeypatch):
+    _stub_tunnel(monkeypatch)
+    logs: list[str] = []
+    stopped: list[bool] = []
+    run_tunnel(
+        _Cfg(),
+        "1.2.3.4",
+        log=logs.append,
+        stop_gpu=lambda: stopped.append(True),
+        session_end_poll=lambda _t: True,
+        poll_seconds=999,
+    )
+    assert stopped == [True]
+    assert any("GPU остановлен" in x for x in logs)
+
+
+def test_run_tunnel_ctrl_c_keeps_gpu(monkeypatch):
+    _stub_tunnel(monkeypatch)
+    logs: list[str] = []
+    stopped: list[bool] = []
+
+    def boom() -> None:
+        raise KeyboardInterrupt
+
+    run_tunnel(
+        _Cfg(),
+        "1.2.3.4",
+        log=logs.append,
+        wait=boom,
+        stop_gpu=lambda: stopped.append(True),
+    )
+    assert stopped == []
+    assert any("GPU жив" in x for x in logs)