Cashu: enable multi-mint sends

[kaloudis]

Currently, on the cashu branch, you can only send from one mint at a time. Let's investigate the ability to do multi-mint sends.

[a-khushal]

@kaloudis the tokenObj in the mintToken function currently has only a single mint and proofs

const tokenObj = {
    mint: mintUrl,
    proofs: proofsToSend,
    memo,
    unit: 'sat'
}; 

can we make this to have multiple mint and proofs like this?

const tokenObj = {
  token: [
    {
      mint: mintUrl1,
      proofs: proofsFromMint1,
    },
    {
      mint: mintUrl2,
      proofs: proofsFromMint2,
    },
    {
      mint: mintUrl3,
      proofs: proofsFromMint3,
    },
  ],
  memo,
  unit: 'sat'
};

and we can let the user select multiple mints by modifying the views/Cashu/Mints.tsx

[a-khushal]

I think the above solution is incorrect, we probably have to implement Partial multi-path payments https://github.com/cashubtc/nuts/blob/4b86b0ca606f7a4825a2308d1a127dda9741ae8f/15.md

[kaloudis]

https://x.com/callebtc/status/1930701784722350316

[a-khushal]

thank you @kaloudis will work on it.