fixed analytics unable to display empty string + fixed unable to redirect custom domain

frontend/src/routes/(app)/dashboard/links/[id]/+page.svelte

@@ -302,7 +302,7 @@
 							<div class="flex items-center justify-between">
 								<div class="flex items-center gap-4">
 									<TabletSmartphone />
-									<div>{visitorByOS.os ?? '(None)'}</div>
+									<div>{visitorByOS.os || '(None)'}</div>
 								</div>
 								<div>
 									{visitorByOS.count}
@@ -330,7 +330,7 @@
 								<div class="flex items-center gap-4">
 									<GlobeIcon />
 									<div>
-										{visitorByBrowser.browser ?? '(None)'}
+										{visitorByBrowser.browser || '(None)'}
 									</div>
 								</div>
 								<div>

redirect/main.go

@@ -127,7 +127,7 @@ func main() {
 		} else {
 			shortener, err := queries.GetShortenerWithDomain(ctx, db.GetShortenerWithDomainParams{
 				Code:         code,
-				CustomDomain: pgtype.Text{String: domain},
+				CustomDomain: pgtype.Text{String: domain, Valid: true},
 			})
 			shortenerId = shortener.ID
 			if err != nil {