Upgrade to react-admin v5

[djhi]

Tests won't pass until we provide a token in the repository actions settings

[fzaninotto]

I'd make only one job with both typecheck and test, as most of the job time is spent initializing

[fzaninotto]

I have a few UI issues.

• The dark theme isn't legible in some pages:

• we need to add the theme switcher back to the appbar, and default to light theme
• The user menu isn't vertically centered in the appbar
  
• the tanstack query devtools icon is too large

[fzaninotto]

2 things are still missing:

• default to light theme
• the tanstack query devtools icon is too large

[djhi]

default to light theme

Why not let the user system decide?

[fzaninotto]

Why not let the user system decide?

Because the dark theme of this app isn't very nice IMHO