feat(investigations): add event impact and work-order feedback flows

Add isolated burst and pollution impact evidence, parallel work-order workflows, persisted notifications and graph updates.

Checkpoint current code. Known follow-ups remain for large pollution result previews and graceful geometry failure.

tests/unit/test_mcp_query.py

@@ -373,6 +373,30 @@ def test_replay_binding_denies_future_and_allows_device_metadata(monkeypatch):
     asyncio.run(query_service.authorize_query(SimpleNamespace(project=object()), bound, TOOLS["list_scada_devices"], SimpleNamespace()))
 
 
+def test_replay_burst_scenario_requires_coverage_permission_and_known_start(monkeypatch):
+    bound = binding(task=True)
+    bound.replay_context = {"knowledge_cutoff": "2026-10-08T01:00:00Z"}
+    permissions = PERMISSIONS | {"simulation.run", "scada.view", "simulation.view"}
+    bound.permission_cap = sorted(permissions)
+    monkeypatch.setattr(query_service, "permissions_for_context", lambda _: permissions)
+    scope = SimpleNamespace(project=SimpleNamespace(project_role="member"))
+    args = TOOLS["run_burst_simulation"].model.model_validate({
+        "context_handle": bound.context_handle, "start_time": "2026-10-08T01:00:00Z",
+        "output_node_ids": ["J1"], "burst_pipe_ids": ["P1"], "orifice_areas_cm2": [2],
+        "include_impact_coverage": True,
+    })
+    asyncio.run(query_service.authorize_query(scope, bound, TOOLS["run_burst_simulation"], args))
+    for changed, status in (({"include_impact_coverage": False}, 422),
+                            ({"start_time": datetime(2026, 10, 8, 2, tzinfo=timezone.utc)}, 422)):
+        with pytest.raises(HTTPException) as error:
+            asyncio.run(query_service.authorize_query(scope, bound, TOOLS["run_burst_simulation"], args.model_copy(update=changed)))
+        assert error.value.status_code == status
+    bound.permission_cap = sorted(permissions - {"simulation.view"})
+    with pytest.raises(HTTPException) as error:
+        asyncio.run(query_service.authorize_query(scope, bound, TOOLS["run_burst_simulation"], args))
+    assert error.value.status_code == 403
+
+
 def test_model_response_displays_utc8_without_changing_query_instants_or_source(runtime):
     app, client, _, _ = runtime
     at = datetime(2026, 12, 31, 16, tzinfo=timezone.utc)