Closes#590
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* **Tests**
* Enhanced test coverage for backup pattern handling and anchoring
* Added end-to-end scenarios validating include patterns, exclusion patterns, and exclude-if-present functionality
* **Refactor**
* Updated pattern processing logic to improve relative path resolution for backup patterns
* Improved asynchronous handling in backup initialization workflow
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Allows users to pass arbitrary restic flags via a new advanced section in the create/edit schedule form. Includes DB migration, schema update, DTO, service, and restic command changes.
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## Summary by CodeRabbit
* **Tests**
* Improved test infrastructure and organization across backup, repository, volume, and utility modules with streamlined mock setup and cleaner test patterns.
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refactor(restic): split each command into its own file
refactor: add missing await before promise expects
<!-- This is an auto-generated comment: release notes by coderabbit.ai -->
## Summary by CodeRabbit
## Release Notes
* **Tests**
* Improved async assertion handling across test suites for enhanced test reliability
* Expanded test coverage for backup, restore, and other core operations
* **Refactor**
* Reorganized internal utility structure for improved code maintainability
* **Chores**
* Updated linting configuration and TypeScript dependencies
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