Add loading ui on topbar

Psk on a l'impression d'être déco sinon

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• Location: https://churros.app/documents/sdn/2a-fise/
• Logged-in: Yes
• Version: 1.64.0-rc.1
• Build: 0ed2467e
• Browser: Chrome v126.0.0.0 (engine Blink v126.0.0.0)
• OS: Android v10
• Device: mobile unknown K (arch unknown)
• ScreenSize: 412 x 839