docs: fix dead links in README.md

[rebustron]

Description

Hi! I fixed outdated and incorrect paths in README.md, ensuring all internal links point to the correct locations.

Changes:

• Removed: persist crate reference Refactor wallet and persist mod, remove bdk_persist crate #1454
• Fixed: Incorrect paths for example projects:
  • wallet_esplora_blocking → example_wallet_esplora_blocking
  • wallet_esplora_async → example_wallet_esplora_async
  • wallet_electrum → example_wallet_electrum

Checklists

All Submissions:

• I've signed all my commits
• I followed the contribution guidelines
• I ran cargo fmt and cargo clippy before committing

New Features:

• I've added tests for the new feature
• I've added docs for the new feature

Bugfixes:

• This pull request breaks the existing API
• I've added tests to reproduce the issue which are now passing
• I'm linking the issue being fixed by this PR

[ValuedMammal]

Thank you @rebustron

ACK a245814

Note also that it is preferable to conform to conventional commits style.

[oleonardolima]

ACK a245814