tapfreighter: unlock inputs on err if not in broadcast complete state

Update unlock logic to ensure that errors encountered during the
anchor tx broadcast process, but before reaching the broadcast complete
state, result in coins being unlocked. This prevents assets from
remaining locked in case of intermediate failures.

Author: ffranr

tapfreighter/chain_porter.go

@@ -1487,7 +1487,7 @@ func (p *ChainPorter) unlockInputs(ctx context.Context, pkg *sendPackage) {
 	// sanity-check that we have known input commitments to unlock, since
 	// that might not always be the case (for example if another party
 	// contributes inputs).
-	if pkg.SendState < SendStateStorePreBroadcast &&
+	if pkg.SendState < SendStateBroadcastComplete &&
 		len(pkg.InputCommitments) > 0 {
 
 		for prevID := range pkg.InputCommitments {