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_verify_stack.py

@@ -95,6 +95,35 @@ def test_verify_gpu_env_ok(monkeypatch):
     assert any("GPU-стека" in line for line in logs)
 
 
+def test_verify_gpu_env_fail_fast_cuda(monkeypatch):
+    import json
+
+    import gpu_rent.ssh_ops as ssh_ops
+
+    payload = {
+        "ok": False,
+        "checks": [
+            {"name": "nvidia-smi", "required": True, "ok": True, "detail": "ok"},
+            {"name": "cuda", "required": True, "ok": False, "detail": "нет libcuda"},
+            {"name": "torch", "required": True, "ok": False, "detail": "no venv"},
+        ],
+    }
+    calls = {"n": 0}
+
+    def fake(*a, **k):
+        calls["n"] += 1
+        return json.dumps(payload)
+
+    monkeypatch.setattr(ssh_ops, "run_python", fake)
+    logs: list[str] = []
+    try:
+        verify_gpu_env(_Cfg(), "1.2.3.4", logs.append, timeout=600.0, poll_every=0.1)
+        assert False, "expected CloudError"
+    except CloudError as exc:
+        assert "fail-fast" in str(exc).lower() or "cuda" in str(exc).lower()
+    assert calls["n"] == 1
+
+
 def test_verify_gpu_env_fails_without_cuda(monkeypatch):
     import json