feat(ui): polish invite preview card copy

src/app/components/ContentLinkBlock.svelte

@@ -5,8 +5,15 @@
   import Link from "@lib/components/Link.svelte"
   import ContentLinkDetail from "@app/components/ContentLinkDetail.svelte"
   import ContentLinkBlockImage from "@app/components/ContentLinkBlockImage.svelte"
+  import RelaySummary from "@app/components/RelaySummary.svelte"
   import {pushModal} from "@app/util/modal"
-  import {dufflepud, PLATFORM_URL, IMAGE_CONTENT_TYPES, VIDEO_CONTENT_TYPES} from "@app/core/state"
+  import {
+    dufflepud,
+    PLATFORM_URL,
+    IMAGE_CONTENT_TYPES,
+    VIDEO_CONTENT_TYPES,
+    parseInviteLink,
+  } from "@app/core/state"
   import {makeSpacePath} from "@app/util/routes"
 
   const {value, event} = $props()
@@ -14,6 +21,7 @@
   let hideImage = $state(false)
 
   const url = value.url.toString()
+  const inviteData = parseInviteLink(url)
   const fileType = getTagValue("file-type", event.tags) || ""
   const [href, external] = call(() => {
     if (isRelayUrl(url)) return [makeSpacePath(url), false]
@@ -49,6 +57,11 @@
       <button type="button" onclick={stopPropagation(preventDefault(expand))}>
         <ContentLinkBlockImage {value} {event} class="m-auto max-h-96 rounded-box" />
       </button>
+    {:else if inviteData}
+      <div class="bg-alt flex max-w-xl flex-col gap-4 p-4 leading-normal">
+        <p class="text-sm opacity-75">Invitation to join a space:</p>
+        <RelaySummary url={inviteData.url} />
+      </div>
     {:else}
       {#await loadPreview()}
         <div class="center my-12 w-full">