Managing deactivated features on blindbit backend

[pythcoiner]

I see in blindbit config that there is several "modes" related to dust/cutthrough: https://github.com/setavenger/blindbit-oracle/blob/7e7a0e32e2ff3e1c97182a4723b1ce60335cc2f9/src/common/config.go#L45

I think it should be good to get this via the info endpoint when the client connect and either:

1. error if parameter passed to get_block_data_for_range() are not compatible with the server config
2. silently fallback to the better option available