• Validate that the Sync All Contracts API(/internal/rpc/syncAllContracts) is fully idempotent.
• Ensure repeated executions correctly synchronize contracts and subscriptions without creating duplicate or inconsistent data.
• Verify data integrity across related tables(contracts, contract_metrics, subscriptions, subscription_measurements).
• Assess whether is_pre_cleanup logic is required for global sync like we have it for 
  /api/swatch-contracts/internal/rpc/sync/contracts/{org_id}

AC:

• Multiple executions of the API do not create duplicate contracts or subscriptions.
• No additional or unintended records are inserted or modified.
• Contracts and subscriptions remain consistent and aligned after each run.
• Clear decision documented on is_pre_cleanup needed or not.
• Automated tests validate repeat-run and already-synced scenarios.