This is "technically" a breaking change, but I'm almost certain no one is using this code yet (including myself). Should I bump the major version just in case? cc @ejball?

• Also fixed some type errors introduced with Support DTO required fields as not optional properties on interface in TS. #69. I'll try to add required field validation on another pass, but since I'm likely the only one working with fastify I'm not too worried about it causing a problem in the mean time.
• Also bumped fastify version to 5.2.1
• Also made fastify plugin "experimental" so I can make additional changes to the api if needed without bumping the major version.