Additional unit tests and coverage.

[shimkiv]

Closes #645 Closes #650

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• Codecov project can be found here: https://app.codecov.io/gh/o1-labs/zkapp-cli
• From now on we will run other CI jobs on the success of Unit tests only.
  • This will allow us to fail faster and save resources.
• CI dependencies were refactored.
  • Publishing on NPM will now be triggered on the success of Unit and Smoke tests.
  • CI dependencies: Common unit tests ← Examples unit tests ← Smoke E2E tests ← Publish to NPM.
• From now on Jest will fail the Unit tests execution in case if resulting coverage will be less than configured threshold.
  • This will force us to write additional Unit tests on main codebase changes.

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• Do we want the Unit tests to be configured as mandatory pre-commit hook (alongside with the currently configured linter)?

[codecov[bot]]

Welcome to Codecov :tada:

Once you merge this PR into your default branch, you're all set! Codecov will compare coverage reports and display results in all future pull requests.

Thanks for integrating Codecov - We've got you covered :open_umbrella:

[shimkiv]

Note for assignee: address TODO in CI config: https://github.com/o1-labs/zkapp-cli/pull/662.

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UPD: Done.

[shimkiv]

https://app.codecov.io/gh/o1-labs/zkapp-cli/tree/feat%2Funit-tests

[shimkiv]

Smoke testing run against this branch: https://github.com/o1-labs/zkapp-cli/actions/runs/9970821097 Please refer to PR's description for the information about why it is not picked up.