Extract `sdk-common` crate

[ok300]

• [x] LNURL-auth
  • extracted sdk-utils for REST utils used in both sdk-lnurl and in the SDK
  • changed LnUrlError::InvalidInvoice from accepting an inner InvoiceError to a simple String, because InvoiceError is not available in sdk-lnurl
  • renamed InputType::LnUrlError to LnUrlEndpointError to avoid naming conflicts with the LnUrlError struct
  • [x] Fix FRB
• [x] LNURL-pay
  • [x] How to handle Payment in LnUrlPaySuccessData?
• [x] LNURL-withdraw
• [x] invoice module
• [x] input_parser module
• [x] Fix tests

[erdemyerebasmaz]

@ok300 Will Fiat Currency module extracted separately, as I believe it relies on server url from Config?

[ok300]

Closes #998