fix: Toleranz bei Relaxationsschranke, Grund bei fehlgeschlagenem Szenario

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

tests/test_feasibility.py

@@ -143,3 +143,9 @@ def test_report_shows_sensitivity_and_integrality_price():
     page = to_html(build_document(result))
     assert "Sensitivität der bindenden Restriktionen" in page and "Preis der Ganzzahligkeit" in page
     assert "0,1" in page.replace(".", ",") or "0.1" in page   # (12100-12000)/1000 = 0.1
+
+
+def test_relaxation_bound_equal_up_to_rounding_is_no_warning():
+    # beobachtet (Portfolio Nr. 2): 0.13896862211718014 gegen 0.13896862211718017
+    run = sens_run([], objective=0.13896862211718017, relaxation=0.13896862211718014)
+    assert check_sensitivity(run, "maximize") == []

tests/test_solver_stage.py

@@ -753,3 +753,15 @@ def test_ordinary_programs_are_not_suspected():
     from solving.solver_stage import check_generated_data
     code = "import highspy\nh = highspy.Highs()\nDATA = {'kosten': [3, 2]}\n"
     assert check_generated_data(code, SolverCode(code=code, data_assumptions=[])) == []
+
+
+def test_scenario_failing_without_error_text_gets_a_reason():
+    # beobachtet (Portfolio Nr. 2): Szenario ohne Lösung im Zeitlimit, Warnung endete mit leerem Grund
+    from core.model_schema import Scenario
+    from solving.solver_stage import verify_scenarios
+    code = SZENARIO_CODE.replace('    basis = loesen(DATA)\n',
+                                 '    basis = loesen(DATA)\n    if DATA["preis"] > 15:\n'
+                                 '        report("error", None, {})\n        return\n')
+    run = run_solver_code(code)
+    befunde = verify_scenarios(run, code)
+    assert any("doppelter Preis" in b and "ohne Fehlertext" in b for b in befunde)