multi: extend InvoiceDB methods with a context argument (#8066)

* multi: extend InvoiceDB methods with a context argument

This commit adds a context to InvoiceDB's methods. Along this refactor
we also extend InvoiceRegistry methods with contexts where it makes
sense. This change is essential to be able to provide kvdb and sqldb
implementations for InvoiceDB.

* channeldb: restrict invoice tests to only use an InvoiceDB instance

* docs: update release notes for 0.18.0

htlcswitch/interfaces.go

@@ -1,6 +1,8 @@
 package htlcswitch
 
 import (
+	"context"
+
 	"github.com/btcsuite/btcd/wire"
 	"github.com/lightningnetwork/lnd/channeldb"
 	"github.com/lightningnetwork/lnd/channeldb/models"
@@ -17,7 +19,7 @@ import (
 type InvoiceDatabase interface {
 	// LookupInvoice attempts to look up an invoice according to its 32
 	// byte payment hash.
-	LookupInvoice(lntypes.Hash) (invoices.Invoice, error)
+	LookupInvoice(context.Context, lntypes.Hash) (invoices.Invoice, error)
 
 	// NotifyExitHopHtlc attempts to mark an invoice as settled. If the
 	// invoice is a debug invoice, then this method is a noop as debug
@@ -33,10 +35,10 @@ type InvoiceDatabase interface {
 
 	// CancelInvoice attempts to cancel the invoice corresponding to the
 	// passed payment hash.
-	CancelInvoice(payHash lntypes.Hash) error
+	CancelInvoice(ctx context.Context, payHash lntypes.Hash) error
 
 	// SettleHodlInvoice settles a hold invoice.
-	SettleHodlInvoice(preimage lntypes.Preimage) error
+	SettleHodlInvoice(ctx context.Context, preimage lntypes.Preimage) error
 
 	// HodlUnsubscribeAll unsubscribes from all htlc resolutions.
 	HodlUnsubscribeAll(subscriber chan<- interface{})