fix: adjust cursor handling for KV pagination

Moves undefined fallback from client to server side for cursor parameter
Ensures consistent pagination behavior when fetching links from KV storage

This prevents potential edge cases where undefined cursor values could be handled differently between client and server.

components/dashboard/links/Index.vue

@@ -11,7 +11,7 @@ async function getLinks() {
   const data = await useAPI('/api/link/list', {
     query: {
       limit,
-      cursor: cursor || undefined,
+      cursor,
     },
   })
   links.value = links.value.concat(data.links).filter(Boolean) // Sometimes cloudflare will return null, filter out

server/api/link/list.get.ts

@@ -10,7 +10,7 @@ export default eventHandler(async (event) => {
   const list = await KV.list({
     prefix: `link:`,
     limit,
-    cursor,
+    cursor: cursor || undefined,
   })
   if (Array.isArray(list.keys)) {
     list.links = await Promise.all(list.keys.map(async (key: { name: string }) => {