refactor: fix type inconsistency and more

[michalsn]

Description
This PR is based on @kenjis PR: #11. It fixes some more errors catched by phpstan and adds slightly better validation for command options.

Since these are valid calls, I had to suppress calls to methods: QueueJobFailedModel::affectedRows() and QueueJobFailedModel::truncate(). I guess phpstan can't get what we do in the model.

Checklist:

• Securely signed commits
• Component(s) with PHPDoc blocks, only if necessary or adds value
• Unit testing, with >80% coverage
• User guide updated
• Conforms to style guide