Enhance SwarmUI integration and GPU environment verification

- Updated CLI documentation to reflect the new handling of `CIVITAI_API_TOKEN`, which is now automatically passed to SwarmUI user settings during startup.
- Improved the `render_access_panel` function to include additional warnings for idle-killer failures and stack errors, enhancing user feedback.
- Introduced a new function `seed_swarmui_api_keys` to manage API key injection into SwarmUI, ensuring seamless integration with the Model Downloader.
- Enhanced GPU environment verification logic to include fail-fast checks for critical components like CUDA, improving error handling and user notifications.
- Updated tests to validate the new API key handling and access panel behavior, ensuring robustness in the integration process.

tests/test_timing.py

@@ -0,0 +1,33 @@
+from gpu_rent.timing import PhaseTimes, WaitLog, format_duration
+
+
+def test_format_duration():
+    assert format_duration(5) == "5s"
+    assert format_duration(65) == "1m 5s"
+    assert format_duration(60) == "1m"
+    assert format_duration(3661) == "1h 1m"
+
+
+def test_phase_times_summary(monkeypatch):
+    times = iter([100.0, 110.0, 130.0, 190.0])
+    monkeypatch.setattr("gpu_rent.timing.time.monotonic", lambda: next(times))
+    clock = PhaseTimes()
+    clock.mark("SSH")
+    clock.mark("bootstrap")
+    line = clock.summary_line()
+    assert "SSH 10s" in line
+    assert "bootstrap 20s" in line
+    assert "всего" in line
+
+
+def test_wait_log_throttles(monkeypatch):
+    logs: list[str] = []
+    t = {"now": 0.0}
+    monkeypatch.setattr("gpu_rent.timing.time.monotonic", lambda: t["now"])
+    w = WaitLog(logs.append, every=30.0)
+    w.tick("a")
+    t["now"] = 10.0
+    w.tick("b")
+    t["now"] = 31.0
+    w.tick("c")
+    assert logs == ["a", "c"]