broadcast transaction observer should catch also transactions signed using legacy serialization

src/bot.ts

@@ -95,7 +95,13 @@ export class WorkerBee implements IWorkerBee {
 
     return {
       subscribe: observer => {
-        const listener = this.observe.onTransactionId(apiTx.id).provideBlockHeaderData().subscribe({
+		const txId = apiTx.id;
+		let txObserver = this.observe.onTransactionId(txId);
+		const legacyId = apiTx.legacy_id;
+		if(legacyId !== apiTx.id)
+		  txObserver = txObserver.or.onTransactionId(legacyId);
+
+		const listener = txObserver.provideBlockHeaderData().subscribe({
           next(val) {
             observer.next?.({
               transaction: val.transactions[apiTx.id]!,