Add index field to IndexedTx

[webmaster128]

Index is the position within a block. This is lost here:

  private async txsQuery(query: string): Promise<readonly IndexedTx[]> {
    const results = await this.forceGetTmClient().txSearchAll({ query: query });
    return results.txs.map((tx) => {
      // tx.index should be used too
      return {
        height: tx.height,
        hash: toHex(tx.hash).toUpperCase(),
        code: tx.result.code,
        events: tx.result.events.map(fromTendermint34Event),
        rawLog: tx.result.log || "",
        tx: tx.tx,
        gasUsed: tx.result.gasUsed,
        gasWanted: tx.result.gasWanted,
      };
    });
  }