Touched up notebooks + webapp

tests/test_webapp.py

@@ -0,0 +1,82 @@
+from fastapi.testclient import TestClient
+
+from webapp.app import app
+
+
+client = TestClient(app)
+
+
+def test_health_endpoint():
+    response = client.get("/api/health")
+    assert response.status_code == 200
+    payload = response.json()
+    assert payload["ok"] is True
+    assert payload["version"] == "0.4.7"
+
+
+def test_simulation_endpoint_preserves_equal_budget():
+    response = client.post(
+        "/api/simulate",
+        json={
+            "rng_seed": 3,
+            "n_paths": 5,
+            "n_steps": 100,
+            "drop_fraction": 0.05,
+            "rise_fraction": 0.08,
+            "max_detection_lag_steps": 3,
+        },
+    )
+    assert response.status_code == 200
+    payload = response.json()
+    assert payload["adaptive_total_samples"] == payload["fixed_total_samples"]
+    assert payload["max_detection_lag_steps"] == 3
+
+def test_webapp_imports_from_source_checkout_without_installed_package(tmp_path):
+    """The documented direct uvicorn command must resolve the src-layout package."""
+    import os
+    import subprocess
+    import sys
+    from pathlib import Path
+
+    repo_root = Path(__file__).resolve().parents[1]
+    env = os.environ.copy()
+    env.pop("PYTHONPATH", None)
+    completed = subprocess.run(
+        [sys.executable, "-c", "import webapp.app; print(webapp.app.app.title)"],
+        cwd=repo_root,
+        env=env,
+        capture_output=True,
+        text=True,
+        check=False,
+    )
+    assert completed.returncode == 0, completed.stderr
+    assert "Adaptive Barrier Monitor" in completed.stdout
+
+
+
+def test_simulation_endpoint_supports_fixed_cadence():
+    response = client.post(
+        "/api/simulate",
+        json={
+            "rng_seed": 3,
+            "n_paths": 5,
+            "n_steps": 200,
+            "window_minutes": 200.0,
+            "dt_cap_minutes": 2.0,
+            "comparison_mode": "fixed_cadence",
+            "fixed_cadence_minutes": 20.0,
+        },
+    )
+    assert response.status_code == 200
+    payload = response.json()
+    assert payload["comparison_mode"] == "fixed_cadence"
+    assert payload["fixed_cadence_minutes"] == 20.0
+    assert payload["adaptive_total_samples"] != payload["fixed_total_samples"]
+
+
+def test_simulation_endpoint_rejects_unknown_comparison_mode():
+    response = client.post(
+        "/api/simulate",
+        json={"comparison_mode": "unknown"},
+    )
+    assert response.status_code == 422