fix: compile error with optional nuts

[ngutech21]

running "just build" local results in multiple compile errors. This is a fix for the first one:

error[E0599]: no method named check_spendablefound for structcashu_sdk::client::blocking::Clientin the current scope --> bindings/cashu-sdk-ffi/src/client.rs:97:18 | 96 | / ... self.inner 97 | | ... .check_spendable(&proofs.iter().map(|p| p.as_ref().deref().clone()).collect())? | | -^^^^^^^^^^^^^^^ method not found inClient`
| |___________|
|

error[E0599]: no method named get_info found for struct cashu_sdk::client::blocking::Client in the current scope
--> bindings/cashu-sdk-ffi/src/client.rs:103:32
|
103 | Ok(Arc::new(self.inner.get_info()?.into()))
| ^^^^^^^^ method not found in Client
`
I think CI didn't catch this one, because CI never builds the full workspace without any feature flags like "just build" does.

[thesimplekid]

I'm working on fixing up optional features as I'm working on NUT11 and NUT12. The blocking client one is a weird one that has pop up recently that i haven't' figured out myself. Eventually I will make the FFI bindings async and wont need the blocking client.

[thesimplekid]

just build is working for me on main now after refactoring the client. Let me know if you're still running into issues

[ngutech21]

Everything works fine. Thank you