chore: apply linting fixes and expand ruff coverage to test suite

tests/test_stability_detector.py

@@ -1,8 +1,10 @@
 from pygui.backend.models.stability_detector import (
-    StabilityDetector, STATE_IDLE, STATE_RAMP, STATE_SET,
+    STATE_IDLE,
+    STATE_RAMP,
+    STATE_SET,
+    StabilityDetector,
 )
 
-
 SET_POINT = 149.0
 
 def make():
@@ -11,16 +13,16 @@ def make():
 def test_idle_when_cold():
     d = make()
     assert d.update(avg=25.0, time=0.0, set_point=SET_POINT) == STATE_IDLE
-    
+
 def test_ramp_while_far_from_setpoint():
     d = make()
     d.update(avg=100.0, time=0.0, set_point=SET_POINT)
-    
+
 def test_ramp_until_settle_time_elapses():
     d = make()
     assert d.update(avg=149.2, time=0.0, set_point=SET_POINT) == STATE_RAMP
     assert d.update(avg=148.9, time=0.0, set_point=SET_POINT) == STATE_RAMP
-    
+
 def test_set_after_holding_near_setpoint():
     d = make()
     d.update(avg=149.2, time=0.0, set_point=SET_POINT)
@@ -32,4 +34,4 @@ def test_back_to_ramp_on_disturbance():
     d = make()
     for t in (0.0, 1.0, 2.5):
         d.update(149.0, t, set_point=SET_POINT)
-    assert d.update(avg=160.0, time=3.0, set_point=SET_POINT) == STATE_RAMP
+    assert d.update(avg=160.0, time=3.0, set_point=SET_POINT) == STATE_RAMP