<!-- This is an auto-generated comment: release notes by coderabbit.ai -->
## Summary by CodeRabbit
- **New Features**
- Added a GraphQL mutation to validate multiple app configuration updates, returning detailed validation results for each item.
- Extended the API schema to support validation feedback, enabling client-side checks before applying changes.
- Introduced a detailed, parameterized error message system for configuration validation errors.
- Enabled validation of configuration inputs via the admin UI with clear, descriptive error messages.
- **Improvements**
- Enhanced error reporting with specific, context-rich messages for invalid app configurations.
- Simplified admin settings UI by removing the confirmation dialog and streamlining save actions.
- Improved clarity and maintainability of validation logic and error handling components.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
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