Spawn emulator per test

[notmandatory]

Description

• Added coinkite/coinkite-tap-protocol git submodule
• Added Justfile to setup the Python venv for coinkite-tap-protocol card emulator
• Added emulator::EcardSubprocess to spawn a thread with a card emulator for each test on a unique unix pipe
• Updated tests to use the EcardSubprocess
• Added new sats_chip module and SatsChip struct
• Added new TapSignerShared trait for functions shared between TapSigner and SatsChip
• Fixed test_new_command test to verify it recognizes the difference between TapSigner and SatsChip
• Updated CI to separate building from testing and to use the emulator for tests.
• Add new test for the check_certificate command

Notes to the reviewers

You can use the recipe just test-lib to setup the emulator python venv and run the tests.

Changelog notice

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