fix: resolve media permission bugs and improve device access UX

[obrucheoghene]

• Fix requestCameraPermission filtering audioinput instead of videoinput
• Fix toggleMic calling requestCameraPermission instead of requestMicPermission
• Replace alert() calls with sonner toast.error() using structured title/description
• Show toast when requestCameraAndMicPermissions is denied (was silently swallowed)
• Add proactive navigator.permissions check on pre-join screen with actionable denied toast
• Add micPending/cameraPending loading state; show spinner on buttons during acquisition

Pull Request for Mitsi

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Description

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Related Issues

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