Glossary updates

[sptramer]

We need to make sure that the glossary in the documentation is up to date and accurate - O3DE uses largely standard industry terms but does have some of its own quirks. SIG needs to review this issue to assign work and get engineers involved in assisting with the term updates.

[willihay]

https://www.o3de.org/docs/user-guide/appendix/glossary/