* chore: migrate to vitest
* test: speed up some suites by sharing sessions and mocking expensive non-tested actions
* test: refactor some tests to verify behavior instead of implementation details
* chore: fix linting issues
<!-- This is an auto-generated comment: release notes by coderabbit.ai -->
## Summary by CodeRabbit
* **Tests**
* Improved test infrastructure and organization across backup, repository, volume, and utility modules with streamlined mock setup and cleaner test patterns.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
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
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
