feat: Implement final type safety fixes

src/hooks/useUnitPreferences.ts

@@ -11,7 +11,7 @@ function isValidUnitPreferences(obj: unknown): obj is UnitPreferences {
     typeof obj === 'object' &&
     obj !== null &&
     'measurement_system' in obj &&
-    ['metric', 'imperial'].includes((obj as any).measurement_system)
+    (obj.measurement_system === 'metric' || obj.measurement_system === 'imperial')
   );
 }