71fff1613d1c167d180636857063e181f6acedf1 feat(chain): add txout methods to `KeychainTxOutIndex` (志宇)
83e7b7ec402bef27c3f83876f346ec2abd23eff1 docs(chain): improve `KeychainTxOutIndex` docs (志宇)
9294e30943f3f79bb36915d69652d9086323131f docs(wallet): improve docs for unbounded spk iterator methods (志宇)
b74c2e262255a39e9dc904aad469e307bf7d0151 fix(wallet): use efficient peek address logic (志宇)
81aeaba48a980a7e7add76ac2d24e896bedaa1d2 feat(chain): add `SpkIterator::descriptor` method (志宇)
c7b47af72f278ba73abea58db49cff1245428f97 refactor(chain)!: revamp `KeychainTxOutIndex` API (志宇)
705690ee8fddba8517d907183b7ddfeafb633609 feat(chain): make output of `SpkTxOutIndex::unused_spks` cloneable (志宇)
Pull request description:
Closes#1268
### Description
Previously `SpkTxOutIndex` methods can be called from `KeychainTxOutIndex` due to the `DeRef` implementation. However, the internal `SpkTxOut` will also contain lookahead spks resulting in an error-prone API.
`SpkTxOutIndex` methods are now not directly callable from `KeychainTxOutIndex`. Methods of `KeychainTxOutIndex` are renamed for clarity. I.e. methods that return an unbounded spk iter are prefixed with `unbounded`.
In addition to this, I also optimized the peek-address logic of `bdk::Wallet` using the optimized `<SpkIterator as Iterator>::nth` implementation.
### Notes to the reviewers
This is mostly refactoring, but can also be considered a bug-fix (as the API before was very problematic).
### Changelog notice
Changed
* Wallet's peek-address logic is optimized by making use of `<SpkIterator as Iterator>::nth`.
* `KeychainTxOutIndex` API is refactored to better differentiate between methods that return unbounded vs stored spks.
* `KeychainTxOutIndex` no longer directly exposes `SpkTxOutIndex` methods via `DeRef`. This was problematic because `SpkTxOutIndex` also contains lookahead spks which we want to hide.
Added
* `SpkIterator::descriptor` method which gets a reference to the internal descriptor.
### Checklists
#### All Submissions:
* [x] I've signed all my commits
* [x] I followed the [contribution guidelines](https://github.com/bitcoindevkit/bdk/blob/master/CONTRIBUTING.md)
* [x] I ran `cargo fmt` and `cargo clippy` before committing
#### New Features:
~* [ ] I've added tests for the new feature~
* [x] I've added docs for the new feature
#### Bugfixes:
* [x] This pull request breaks the existing API
* [ ] I've added tests to reproduce the issue which are now passing
* [x] I'm linking the issue being fixed by this PR
ACKs for top commit:
danielabrozzoni:
ACK 71fff1613d1c167d180636857063e181f6acedf1
Tree-SHA512: f29c7d2311d0e81c4fe29b8f57c219c24db958194fad5de82bb6d42d562d37fd5d152be7ee03a3f00843be5760569ad29b848250267a548d7d15320fd5292a8f
60abd87a32