Mint: Add clnrest.py Lightning backend (#551)

* log cln error

* return a string

* update corelightningrest to work with latest ver using rune

* fix mpp spec and backend support check

* refactor validation in ledger

* remove weird error

* fix mpp melt model

* corelightningrest.py: Added Multi-Mint payout support
lndrest.py: fix `quote.amount` is not always in sats + better checks

* small fix

* Fix quote.unit str2unit conversion + add missing imports

* settings enable mpp corelightning (default false)

* small fix

* fix `paid_invoice_stream`

* make format

* handle runes

* load rune

* rename to MINT_CORELIGHTNING_REST_RUNE

* try without cert

* port

* try except callback dispatcher

* clean up cln-rest streaming parser

* conftest: mint_corelightning_enable_mpp

* enable mpp in regtest.yaml

* fix error handling clnrest, remove lndrest changes

* CLNRest + CoreLightningRest

* clean up corelightningrest and get last index before starting the stream

* clean up

---------

Co-authored-by: callebtc <93376500+callebtc@users.noreply.github.com>
Co-authored-by: Richard Bensberg <r@coinbatsu.com>

tests/conftest.py

@@ -47,6 +47,7 @@ settings.mint_seed_decryption_key = ""
 settings.mint_max_balance = 0
 settings.mint_transaction_rate_limit_per_minute = 60
 settings.mint_lnd_enable_mpp = True
+settings.mint_clnrest_enable_mpp = False
 settings.mint_input_fee_ppk = 0
 
 assert "test" in settings.cashu_dir