Saved queries: Reconcile right-click menu with vertical "..." menu

[philrz]

Repro is with Brim commit c30f160.

As first pointed out in https://github.com/brimdata/brim/issues/1928#issuecomment-1251634729 and shown in the attached video, as a user I struggled a bit figuring out how to "lock" a query to make it read-only. My first instinct was to right-click on the query in the left panel, but the option was not there. I eventually found my way to the vertical "..." menu. The experience made me realize that we probably need to reconcile these two menus to avoid user confusion. I would propose that we have the same options available in both places to the degree that makes sense.

https://user-images.githubusercontent.com/5934157/191610156-e5fbe45d-be4b-43c5-9ced-9b1fa7535d32.mp4