[CLD-6537] Cloud Annual Renewals - Banners Implementation (#25267)

* Initial implementation of Cloud Annual Renewal flow - system banners for admins and end users

* Actually add the file

* Add AlertBanner to system console billing_subscriptions page

* Fixes for non-admin banner and pipeline

* Updates to coincide with the CWS side of thigns

* Add a feature flag for the 60 day experience to ensure banners don't show accidentally

* Fix tests

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Co-authored-by: Mattermost Build <build@mattermost.com>

webapp/platform/types/src/cloud.ts

@@ -49,6 +49,8 @@ export type Subscription = {
     delinquent_since?: number;
     compliance_blocked?: string;
     billing_type?: string;
+    cancel_at?: number;
+    will_renew?: string;
 }
 
 export type Product = {