This commit migrates the network layer from Retrofit to Ktor.
Specific changes include:
- Replaced Retrofit
with Ktor for network requests.
- Updated dependencies to include Ktor libraries.
- Refactored network service and data classes to use Ktor's API.
- Removed Retrofit-specific code and dependencies.
- Adjusted network module to provide Ktor client and services.
- Updated PixabayImageRepository
to use the new Ktor-based PixabayService.
