feat(dashboard): demo console with web chat, demo clock, scenario playback and split screen

- pages/2_Демо-консоль.py: persona selector, virtual clock bar (+1 h, to 08:00/20:00,
  next day, reset with confirm), fallback patient web chat (buttons from Reply.buttons,
  kind styling, outbox drained after every action and on a 2 s fragment poll), scenario panel
- pages/3_Сплит-экран.py: patient chat or PATIENT_WEB_URL iframe on the left, compact doctor
  panel (patients, live alerts, red banner on a new acute alert) on the right
- console/playback.py: data/synthetic/<persona>.jsonl runner (advance_to/press/text/
  expect_color/start), date chaining between days, pause on failure with retry/skip/manual
- console/api.py: own HTTP client over the frozen API contract, ApiError only

Refs #17

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

tests/test_dashboard_console_pages.py

@@ -0,0 +1,64 @@
+"""Demo console pages (#17) render without crashing even when the API is down (robustness of the live demo)."""
+
+from pathlib import Path
+
+import pytest
+from streamlit.testing.v1 import AppTest
+
+PAGES = Path(__file__).resolve().parents[1] / "dashboard" / "pages"
+
+
+@pytest.fixture
+def api_down(monkeypatch):
+    monkeypatch.setenv("API_BASE_URL", "http://127.0.0.1:9")  # nothing listens on the discard port
+    monkeypatch.setenv("DEMO_PERSONA_TOKEN", "tok-andrey")
+    monkeypatch.delenv("PATIENT_WEB_URL", raising=False)
+
+
+def _page(name: str) -> AppTest:
+    return AppTest.from_file(str(PAGES / name), default_timeout=30)
+
+
+def test_console_page_survives_api_down_and_button_clicks(api_down, tmp_path):
+    scenario = tmp_path / "s.jsonl"
+    scenario.write_text('{"day": 1, "note": "утро", "actions": [{"advance_to": "08:00"}]}\n', encoding="utf-8")
+    at = _page("2_Демо-консоль.py")
+    at.session_state["console_scenario_path:tok-andrey"] = str(scenario)
+    at.run()
+    assert not at.exception
+    assert any("Часы недоступны" in w.value for w in at.warning)
+    labels = [b.label for b in at.button]
+    assert {"+1 час", "Следующий день", "🚀 Начать", "▶ Проиграть день 1"} <= set(labels)
+
+    at.button(key="console-clock-d1").click().run()  # «Следующий день» with the API down
+    assert not at.exception
+    at.button(key="console-chat-start").click().run()
+    assert not at.exception
+    next(b for b in at.button if b.label == "▶ Проиграть день 1").click().run()
+    assert not at.exception
+    state = at.session_state["console_playback:tok-andrey"]
+    assert state.failed is not None and state.done == []  # playback paused, page alive
+    at.run()
+    assert not at.exception
+    assert any("Повторить шаг" in b.label for b in at.button), [b.label for b in at.button]
+
+
+def test_console_page_without_scenario_file(api_down):
+    at = _page("2_Демо-консоль.py")
+    at.session_state["console_scenario_path:tok-andrey"] = "data/synthetic/__missing__.jsonl"
+    at.run()
+    assert not at.exception
+    assert any("Сценарий не загружен" in i.value for i in at.info)
+
+
+def test_split_screen_survives_api_down_and_uses_iframe_when_configured(api_down, monkeypatch):
+    at = _page("3_Сплит-экран.py")
+    at.run()
+    assert not at.exception
+    assert any("Алерты недоступны" in w.value for w in at.warning)
+
+    monkeypatch.setenv("PATIENT_WEB_URL", "http://localhost:5173")
+    at = _page("3_Сплит-экран.py")
+    at.run()
+    assert not at.exception
+    assert any("http://localhost:5173" in c.value for c in at.caption)