readarr replacement

[krojew]

App Addition

• I have opened an issue to discuss this app addition before submitting this pull request.

Description

Adds Readarr to the community train.

[Brief description of what the app does]

App Information

• Upstream: https://github.com/pennydreadful/bookshelf
• Documentation: https://github.com/pennydreadful/bookshelf
• App Version: 0.4.20.91

Testing

Tested locally with:

• [] basic-values.yaml

All tests passed successfully.

Special Notes

• This is a direct replacement for Readarr.
• Couldn't test locally due to environment problems.

Checklist

• App runs successfully locally
• Only modified files under /ix-dev/ or /library/
• README.md included
• Multiple test scenarios tested
• questions.yaml has clear descriptions and follows structure of existing apps
• All automated CI checks pass