Allow central users to use the service catalog

[AdrienClairembault]

Checklist before requesting a review

• I have performed a self-review of my code.
• I have added tests that prove my fix is effective or that my feature works.

Description

Add a menu entry for the service catalog on the central interface and update the various controllers to make sure central user are allowed to use this page.

[cconard96]

Not strictly related to these changes, so not done as a review.

Maybe the menu option should be hidden if there are no forms in the service catalog, or at least have a message shown stating the user doesn't have access to any forms. Right now, the blank page (excluding the header and search box) could be perceived as an error.

[AdrienClairembault]

Maybe the menu option should be hidden if there are no forms in the service catalog

I've thought of it too, but I am unsure how to handle it as for now GLPI's menu is generated once per session so it won't take into account any updates to the content of the service catalog (= the menu won't be removed when the last visible for of an user is disabled or deleted until he logs off).

or at least have a message shown stating the user doesn't have access to any forms. Right now, the blank page (excluding the header and search box) could be perceived as an error.

I have something coming up for this today, which is to add a message when there are no forms found: https://github.com/orgs/glpi-project/projects/7/views/1?pane=issue&itemId=79730580.