feat: check for available updates

frontend/wailsjs/go/main/App.d.ts

@@ -37,6 +37,8 @@ export function BrowseExecutable():Promise<string>;
 
 export function BulkUpdateQSL(arg1:Array<number>,arg2:main.QSLBulkUpdate):Promise<number>;
 
+export function CheckForUpdate():Promise<main.UpdateInfo>;
+
 export function ClearLookupCache():Promise<void>;
 
 export function ClusterSpotStatuses(arg1:Array<main.SpotQuery>):Promise<Array<main.SpotStatus>>;