Mapping bitcoin::txid to dense::txid is a bottleneck

[This map](https://github.com/payjoin/tx-indexer/blob/511c619b56390ae08b0dc7a5add7d049619eed87/src/crates/primitives/src/parser.rs#L213) exists to translate between bitcoin txid types and dense ids when outputs and spent. Its currently unbounded. And hashing the txid again. We need a better solution in general. Taking a look at how blocksci solved this problem is good start