feat: report facts, not warnings (0.2.0)

Drop get_device_warnings. The DSL noise margin and the firmware on offer
are already facts in get_system_config (dsl_downstream_noise_margin,
firmware_update_available, firmware_version); netOrk derives
dsl_snr_low and firmware_update_available from them (netOrk #1111).

tests/unit/test_driver.py

@@ -647,37 +647,14 @@ class TestAutoMaxBitRate:
 
 
 # ---------------------------------------------------------------------------
-# get_device_warnings
+# warnings
 # ---------------------------------------------------------------------------
 
 
-class TestGetDeviceWarnings:
-    def test_returns_empty_list(self, driver):
-        # UI_INFO has UpdateState=Available → one warning expected
-        warnings = driver.get_device_warnings()
-        codes = [w["code"] for w in warnings]
-        assert "firmware_update_available" in codes
-
-    def test_no_firmware_warning_when_no_update(self, driver):
-        driver.fc.call_action.side_effect = lambda svc, act, **kw: (
-            UI_INFO_NO_UPDATE if (svc, act) == ("UserInterface1", "X_AVM-DE_GetInfo")
-            else _call_action(svc, act, **kw)
-        )
-        warnings = driver.get_device_warnings()
-        assert not any(w["code"] == "firmware_update_available" for w in warnings)
-
-    def test_dsl_snr_low_warning(self, driver):
-        low_snr = dict(DSL_INFO, NewDownstreamNoiseMargin=40)  # 4.0 dB < 6 dB threshold
-        driver.fc.call_action.side_effect = lambda svc, act, **kw: (
-            low_snr if (svc, act) == ("WANDSLInterfaceConfig1", "GetInfo")
-            else _call_action(svc, act, **kw)
-        )
-        warnings = driver.get_device_warnings()
-        assert any(w["code"] == "dsl_snr_low" for w in warnings)
-
-    def test_no_dsl_warning_when_snr_ok(self, driver):
-        warnings = driver.get_device_warnings()
-        assert not any(w["code"] == "dsl_snr_low" for w in warnings)
+def test_no_warnings_of_its_own():
+    """The DSL margin and the firmware on offer are facts in get_system_config; the
+    application decides they are warnings (netOrk #1111)."""
+    assert "get_device_warnings" not in vars(FritzBoxDriver)
 
 
 # ---------------------------------------------------------------------------