Improve consistency of title labels across sidebar tabs.

[aaclayton]

Originally in GitLab by @unsoluble1

These are super inconsequential and may even be intentional/opinionated, but:

a) The search field in the Journal Entries sidebar is labelled Search Journal, rather than Seach Journal Entries (which would match the style of all the other sidebar tabs.

b) The tooltips for the Scenes, Actors, and Items tab icons are Scenes Directory etc., rather than just Scenes etc., like the rest.

Suggest picking a standard for each of those and sticking with it across the whole sidebar.

[aaclayton]

marked this issue as related to #6502