Prepare dart package for publishing to pub.dev

[spacebear21]

This updates the dart/ folder structure to enable publishing working bindings to pub.dev

• Add Dart-local Cargo patch config for monorepo development.
  • Patches payjoin-ffi, payjoin, payjoin-test-utils, and payjoin-mailroom to local workspace paths.
• Gate Dart native build _test-utils on the presence of payjoin-ffi/dart/.cargo/config.toml.
  • Local monorepo checkouts include this file, so tests can use test services and shared vectors.
  • The file is excluded from the pub package, so published builds do not enable _test-utils.
• Exclude local-only files from the pub package with .pubignore
• Add package metadata to make dart pub publish --dry-run happy (license, changelog files, homepage and repo links)
• Pin git dependencies by commit rev.
  • payjoin-ffi’s payjoin dependency points at the required rust-payjoin commit.
  • The Dart native wrapper points at the above commit
  • (using commit revs means we can publish immediately to pub.dev without going through a whole rust-payjoin 0.26 release now)
• Add the root Cargo patch for the git payjoin dependency so workspace builds continue using the local payjoin crate.

Remaining steps to publish

   cd payjoin-ffi/dart
   dart pub publish
   git tag payjoin-dart-v0.1.1
   git push origin payjoin-dart-v0.1.1

Pull Request Checklist

Please confirm the following before requesting review:

• I have disclosed my use of
  AI
  in the body of this PR.
• I have read CONTRIBUTING.md and rebased my branch to produce hygienic commits.

[coveralls]

Coverage Report for CI Build 25690074999

Coverage remained the same at 85.294%

Details

• Coverage remained the same as the base build.
• Patch coverage: No coverable lines changed in this PR.
• No coverage regressions found.

Uncovered Changes

No uncovered changes found.

Coverage Regressions

No coverage regressions found.

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Coverage Stats

Relevant Lines:	13668
Covered Lines:	11658
Line Coverage:	85.29%
Coverage Strength:	395.83 hits per line

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💛 - Coveralls

[spacebear21]

Published v0.1.1 https://pub.dev/packages/payjoin from this branch and confirmed it works in the BBM branch SatoshiPortal/bullbitcoin-mobile#2041

[benalleng]

TACK via SatoshiPortal/bullbitcoin-mobile#1978
payjoin-cli sreceiver <-> bb mobile sender
https://mempool.space/testnet/tx/85ffa27c0b9a679775ca3ed78420c57b75dac48a8fbe1e692959073eeb8601b1