[APP-2160] Build new standard.site link card UI (#10468)

Co-authored-by: vineyardbovines <spencer@thepope.dev>
Co-authored-by: Eric Bailey <git@esb.lol>
Co-authored-by: Claude Opus 4.7 <noreply@anthropic.com>

src/components/Post/Embed/StandardSiteEmbed/publishers.ts

@@ -0,0 +1,52 @@
+import {type AppBskyEmbedExternal} from '@atproto/api'
+
+import {Leaflet} from '#/components/icons/community/Leaflet'
+import {Offprint} from '#/components/icons/community/Offprint'
+import {Pckt} from '#/components/icons/community/Pckt'
+
+export type StandardSitePublisher = {
+  host: string
+  name: string
+  Icon: typeof Leaflet
+}
+
+const STANDARD_SITE_PUBLISHERS: StandardSitePublisher[] = [
+  {host: 'leaflet.pub', name: 'Leaflet', Icon: Leaflet},
+  {host: 'pckt.blog', name: 'pckt', Icon: Pckt},
+  {host: 'offprint.app', name: 'Offprint', Icon: Offprint},
+]
+
+function hostFromUri(uri: string | undefined): string | null {
+  try {
+    return new URL(uri || '').host
+  } catch {
+    return null
+  }
+}
+
+export function getStandardSitePublisherHost(
+  view: AppBskyEmbedExternal.ViewExternal,
+): string | null {
+  return hostFromUri(view.source?.uri)
+}
+
+export function hostMatches(host: string, target: string): boolean {
+  return host === target || host.endsWith('.' + target)
+}
+
+function matchByHost(host: string | null): StandardSitePublisher | null {
+  if (!host) return null
+  return STANDARD_SITE_PUBLISHERS.find(p => hostMatches(host, p.host)) ?? null
+}
+
+export function matchStandardSitePublisher(
+  view: AppBskyEmbedExternal.ViewExternal,
+): StandardSitePublisher | null {
+  return matchByHost(getStandardSitePublisherHost(view))
+}
+
+export function matchStandardSitePublisherByUri(
+  uri: string | undefined,
+): StandardSitePublisher | null {
+  return matchByHost(hostFromUri(uri))
+}