Merge #14150: Add key origin support to descriptors
Summary:
8afb166875 Update documentation to incude origin information (Pieter Wuille)
ff37459abc Add tests for key origin support (Pieter Wuille)
2c6281f180 Add key origin support to descriptors (Pieter Wuille)
Pull request description:
This adds support for [key origin](https://gist.github.com/sipa/e3d23d498c430bb601c5bca83523fa82#key-origin-identification) information to the descriptor parser, and exposes the resulting key path information through `FlatSigningProvider`. There is no observable functionality from this right now, except having the `scantxoutset` RPC accept descriptors that include key origin information. Longer term this feature helps with a potential descriptors-based walletless PSBT updater, or for importing hardware wallet xpubs (once the wallet can import descriptors).
Tree-SHA512: 399828127b2e90a2f32d81ecc30a8a9261d08f4182d5d1744f05e46b25fde1bd383c54835b0820ca668e7d17353fa92c0fb2987e211ce269e0824c9395d210c2
Backport of Core PR14150
Test Plan:
ninja ninja check ninja check-functional
Reviewers: O1 Bitcoin ABC, #bitcoin_abc, deadalnix
Reviewed By: O1 Bitcoin ABC, #bitcoin_abc, deadalnix
Subscribers: deadalnix
Differential Revision: https://reviews.bitcoinabc.org/D6006