Add Git hook to rollback phantom migrations on branch switch

[m-darbinyan]

Closes #18

Description

This PR introduces functionality to automatically rollback phantom migrations when switching branches with git checkout. By default, this feature is disabled. Users can enable it via:

• Environment Variable: export ACTUAL_DB_SCHEMA_GIT_HOOKS_ENABLED=true
• Initializer: ActualDbSchema.config[:git_hooks_enabled] = true

After enabling, users should run the rake task to install the Git hook:
rake actual_db_schema:install_git_hooks

Screenshots

Success

Configuration disabled

.git/hooks directory doesn't exist

post-checkout hook already exists

When hook is up to date

Update

Decline overwrite

...

[ka8725]

@m-darbinyan

I think we are on the right track. I still have some comments. Also, can we utilize the "gem post-install" functionality to run this rake task automatically? After installation, it could ask several questions, such as:

• Would you like to install Git hooks to automatically roll back phantom migrations when switching branches?
• Would you also like to run db:migrate tasks automatically when switching branches?

It would be great to implement the second question as well, even for manual installation. I believe it should be implemented first before addressing the gem post-installation process.

If you have any questions or better ideas, don’t hesitate to reach out to me. Thanks!