The documentation Glossary is limited to GAMMA concepts

[candita]

What would you like to be added:
Move the Glossary page to GAMMA section of docs and retitle as GAMMA Glossary.

https://github.com/kubernetes-sigs/gateway-api/blob/main/site-src/concepts/glossary.md

Why this is needed:

Users/students will misunderstand the terms in the Glossary as applying to traffic that uses xRoutes and Gateways, whereas most of the terminology is from the viewpoint of GAMMA/mesh, which doesn't necessarily use xRoutes or Gateways.

[Hackmey]

Hi, I’ve opened a PR that addresses this issue.
Please have a look and let me know if any changes are needed. Thanks!