refactor: remove service interface files from rqueue-web

Remove duplicate service interface definitions from rqueue-web/src/main/java/com/github/sonus21/rqueue/web/service/ since they now live in rqueue-core:

- RqueueDashboardChartService
- RqueueJobService
- RqueueQDetailService
- RqueueSystemManagerService
- RqueueViewControllerService

The implementation classes in rqueue-web/service/impl remain unchanged, now implementing interfaces from rqueue-core. This completes the architectural refactoring with a single source of truth for service interfaces in rqueue-core.

Assisted-By: Claude Code

Author: sonus21