TRUNK-5950: Part 2 - Implement name column autofill logic

[shivvani-r]

Description

This is Part 2 of the TRUNK-5950 work (Part 1 was merged recently).

This PR adds the logic to automatically populate the mandatory name column based on aIsToB and bIsToA values.

Changes

• Automation: Added a new method updateName() and added @PrePersist and @PreUpdate listeners to auto-generate the name.
• Testing:
  • Added RelationshipTypeTest.java with unit test for updateName() verifying the auto-naming behavior.
  • Updated legacy XML datasets to include the name column (required now that name column cannot be NULL).
• Liquibase: Added a changeset to backfill names for existing rows in the database.

Ticket

https://issues.openmrs.org/browse/TRUNK-5950

Checklist: I completed these to help reviewers :)

• My IDE is configured to follow the code style of this project.
• I have added tests to cover my changes.
• I ran mvn clean package right before creating this pull request and added all formatting changes to my commit.
• All new and existing tests passed.
• My pull request is based on the latest changes of the master branch.

[shivvani-r]

@dkayiwa Thanks for merging the hibernate migrations! This is the follow-up PR that adds the auto-fill logic we discussed here. It's ready for your review when you have a moment.