- Removed redundant `gin.SetMode(gin.TestMode)` calls from individual test files.
- Introduced a centralized `TestMain` function in `testmain_test.go` to set the Gin mode for all tests.
- Ensured consistent test environment setup across various handler test files.
- Implement tests for ImportHandler's Cancel and Commit methods to handle missing and invalid session UUIDs.
- Add tests for ManualChallengeHandler to cover scenarios such as empty challenge ID, provider internal errors, unauthorized access, and challenge not found.
- Enhance error handling in tests to ensure proper responses for various edge cases.
- Implemented `useManualChallenge`, `useChallengePoll`, and `useManualChallengeMutations` hooks for managing manual DNS challenges.
- Created tests for the `useManualChallenge` hooks to ensure correct fetching and mutation behavior.
- Added `ManualDNSChallenge` component for displaying challenge details and actions.
- Developed end-to-end tests for the Manual DNS Provider feature, covering provider selection, challenge UI, and accessibility compliance.
- Included error handling tests for verification failures and network errors.
