Move API related functionality out of views to stores/clients

[PhilBastian]

This is part of #1905

Summary

Refactor frontend state management by extracting API communication logic from Pinia stores into dedicated client modules, and consolidate related functionality into specialized stores.

Changes

• New stores: Created RecoverabilityStore for failed message operations and DeletedMessageGroupsStore for managing deleted message groups
• New API clients: Extracted serviceControlClient and monitoringClient to handle all ServiceControl and Monitoring API calls
• Removed stores: Eliminated ServiceControlStore and EditRetryStore as their functionality has been better organized elsewhere
• Simplified components: Significantly reduced component complexity by moving business logic into stores:
  • DeletedMessageGroups.vue: 255 lines → 42 lines
  • DeletedMessages.vue, FailedMessages.vue, PendingRetries.vue etc. all significantly simplified
• Improved auto-refresh: Enhanced the auto-refresh composable with better state tracking

Benefits

• Better separation between API communication and state management
• More reusable and testable code
• Cleaner, more maintainable components
• Improved organization of related functionality

All existing functionality remains intact with no changes to user-facing features.