feat: Redirect Logged Out Users to Default Group, If It's Public (#2772)

* add default group slug to app info if public

* redirect public user to default group

* added tests

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Co-authored-by: Kuchenpirat <24235032+Kuchenpirat@users.noreply.github.com>

frontend/lib/api/types/admin.ts

@@ -33,6 +33,7 @@ export interface AppInfo {
   version: string;
   demoStatus: boolean;
   allowSignup: boolean;
+  defaultGroupSlug?: string;
 }
 export interface AppStartupInfo {
   isFirstLogin: boolean;