Ensure all data-serialization files end with a single newline character.

Affected file types

• .json
• .yaml
• .yml

Justification

Ensuring that each file ends with exactly one newline follows POSIX conventions (where a line is defined as ending with a newline) and improves consistency across editors and tools. It also prevents unnecessary diffs caused by extra blank lines, keeping version history cleaner and easier to review.

Notes

A Python script was used to apply these changes.