feat: show size for open-source apps

CleanAPK API response contains APK info in a dynamic property named "update_<X>" where X is any integer.

ApplicationDeserializer is modified to parse the property "apk_file_size" from the property "update_<X>". The value contains a string such as 4.05 KiB, 1.23 MiB, etc.

To make the size info consistent with existing UI for Google Play, which shows the size in KB and MB instead of KiB and MiB, size conversion is implemented in BinaryToDecimalSizeConverter, including unit tests.

If there's no correct size information is found, the app details UI will not show any info.