Mainframe Entities - Migration Foundation

**Background**

We are planning to migrating entities (Low Volume Entities - LVEs) and data from the legacy mainframe to the modernized platform. To ensure a consistent, efficient, and low-risk migration approach, a common migration foundation must be established before individual entity migrations begin.

This project delivers the reusable processes, standards, frameworks, and tooling that will support all future migration efforts. By creating a standardized migration methodology, the project reduces implementation effort, improves data quality, minimizes migration risk, and enables repeatable, auditable migrations across all entities.

Note: There is a replica of the Mainframe entities and filings in COLIN performed via manual synchronization process - to be confirmed

**Objectives**

- Define the overall migration strategy, roadmap, and governance approach.
- Create a comprehensive inventory of entities, mainframe data sources, and migration dependencies.
- Establish standardized data mapping, migration, testing, and cutover frameworks.
- Develop reusable migration pipelines and reconciliation processes to validate data integrity.
- Define migration quality standards, including the Definition of Done, validation criteria, and rollback procedures (if any).
- Provide a scalable and repeatable migration foundation that can be leveraged for all subsequent entity migrations.

No files, tests, or entry points are named in the issue. Start by reviewing the migration objectives and defining the inventory, mapping, testing, reconciliation, quality, cutover, and rollback deliverables; done should be a documented, reusable foundation with clear governance and validation criteria.

Written by the indexing model from the issue text.