For #29183
# Checklist for submitter
- [x] Added/updated automated tests
- [x] Manual QA for all new/changed functionality
<!-- This is an auto-generated comment: release notes by coderabbit.ai
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## Summary by CodeRabbit
* **New Features**
* Introduced automated validation workflows for maintained applications
on both macOS and Windows, ensuring apps can be installed, verified, and
uninstalled as expected.
* Added new command-line tool to validate maintained apps, providing
detailed reporting on validation results.
* Enhanced detection and handling of pre-installed applications during
validation.
* Improved post-installation steps for macOS, including quarantine
removal and system refresh.
* **Chores**
* Added new continuous integration workflows to automate application
validation on pull requests for relevant files.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
