Add operation wrapper

Problem

BBO operations need a job processor to handle individual migration execution. Currently there's no mechanism to:

1. Process individual migration jobs queued by the scheduler
2. Set up proper database connection context for each migration
3. Delegate migration execution to the appropriate runner

Solution

Implement an ExecutionWorker that acts as a Sidekiq worker for processing individual migration jobs, similar to the existing BBM pattern.

The worker should:

• Receive (database_name, migration_id) parameters from SingleDatabaseWorker

• Set up the correct database connection context

• Delegate actual migration execution to BatchedMigrationRunner

• Add Wrapper class