[scheduler][joy] Allow to navigate to previous / next time span in every relevant view

[flaviendelangle]

Every view that only render a portion of the time (e.g: a week in the week view) should have a UI to navigate to the previous and to the new portion of time.

It should also have a button to navigate to the portion of time that contains the current date.

Follow up on #17695 (can be done before or after #17696)

In this PR:

• Add an internal state that store the currently visible date
• Create the previous / next button to update the internal state (this UI should use the right time step depending on the current view)
• Create the "Today" button to set the internal state to the current date
• Apply english accessible labels to the buttons (if possible add a "TODO: Add locatization" comment so that we can link them to the localization system when available)

Not in this PR:

• Allow to initialize / control the internal state (can be a follow up)
• Support custom UIs
• Apply localized accessible labels to the buttons (require a localization system that we don't have yet)

Full Calendar:

Bryntum:

Google Calendar:

Notion Calendar: