feat: add RBG backend support for rolling updates

[LikiosSedo]

Summary

Enable rolling update support for ArksApplication and ArksDisaggregatedApplication by integrating RoleBasedGroupSet (RBG) backend while maintaining backward
compatibility with existing LeaderWorkerSet (LWS) applications.

Key Changes

• RBG Backend Integration: Add RBG workload orchestrator support with automatic backend detection
• Rolling Update Support: Enable zero-downtime updates for 6 key fields (Image, CPU, Memory, Replicas, Readiness/Liveness Probes)
• Complete Field Mapping: Map all 27 Pod-level and Container-level InstanceSpec fields to RBGS
• Backward Compatibility: Preserve existing LWS applications, auto-detect backend on reconciliation
• Dual Backend Cleanup: Support deletion for both RBGS and LWS resources

Migration Strategy

• Existing apps: Continue using LWS backend (no changes required)
• New apps: Default to RBG backend with rolling update support
• Migration: Delete and recreate applications to switch from LWS to RBG

Testing

• 6-field rolling updates validated
• Delete-rebuild migration tested
• Backward compatibility confirmed

Dependencies

• Add sigs.k8s.io/rbgs v0.3.4
• Upgrade google.golang.org/grpc v1.67.1 → v1.72.1