Add Craft.cp.announce() and implement for various loading states #7493

Job	Run time
ci / Code Quality / ECS / ECS	31s
ci / Code Quality / PHPStan / PHPStan	2m 29s
ci / Code Quality / Prettier / check	1m 5s
ci / Tests / PHP 8.2 on mysql	10m 56s
ci / Tests / PHP 8.2 on pgsql	15m 3s
ci / Notify Slack	0s
	30m 4s

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