multi: add a rpc endpoint to track the recovery process

lnwallet/interface.go

@@ -285,6 +285,11 @@ type WalletController interface {
 	// known to the wallet, expressed in Unix epoch time
 	IsSynced() (bool, int64, error)
 
+	// GetRecoveryInfo returns a boolean indicating whether the wallet is
+	// started in recovery mode. It also returns a float64 indicating the
+	// recovery progress made so far.
+	GetRecoveryInfo() (bool, float64, error)
+
 	// Start initializes the wallet, making any necessary connections,
 	// starting up required goroutines etc.
 	Start() error