changed the method of generating assets to be more declrative when it comes to names of the assets.
it now include the file path name e.g (asset in the path "assets/images/home-images/home.png" will be generated as this "String assetsImagesHomeImageshome = "path" ".
this will be very helpful in the future when we want to orgnize the assets dir.
Move fan speed and temperature mode logic to the DevicesCubit for better
separation of concerns and improved code readability. Update widget to use
BlocBuilder for state management and simplify control logic.
