Fix linting and type errors for CI

- Use X | None syntax instead of Optional[X] (UP045)
- Sort imports in dashboard app (I001)
- Remove unnecessary UTF-8 encoding argument (UP012)
- Add 'from err' to exception re-raises (B904)
- Remove unused imports in integration tests (F401)
- Fix useless expression in test (B018)
- Cast **1.5 result to float in LDO model (mypy no-any-return)
- Use functools.partial instead of lambda in server (mypy misc)

tests/unit/test_physics_models.py

@@ -63,7 +63,7 @@ class TestThermalState:
 
         # Should not raise
         hash(state)
-        {state}  # Can be added to a set
+        _ = {state}  # Can be added to a set
 
 
 class TestElectricalState: