feat: user relay management, blog naddr sync, and OG image update

Add UserRelay API and dashboard relays tab with NIP-65 import, store post
naddr for Nostr articles, and ship Prisma migrations for board tables,
user relays, and post metadata.

Co-authored-by: Cursor <cursoragent@cursor.com>

frontend/components/public/JsonLd.tsx

@@ -24,7 +24,7 @@ export function OrganizationJsonLd() {
         url: siteUrl,
         logo: `${siteUrl}/og-default.png`,
         description:
-          "Belgium's sovereign Bitcoin community. Monthly meetups, education, and curated Nostr content.",
+          "Discover Bitcoin meetups across Belgium. Real conversations, education, and a strong local community.",
         sameAs: ["https://t.me/belgianbitcoinembassy"],
         address: {
           "@type": "PostalAddress",
@@ -45,7 +45,7 @@ export function WebSiteJsonLd() {
         name: "Belgian Bitcoin Embassy",
         url: siteUrl,
         description:
-          "Belgium's sovereign Bitcoin community. Monthly meetups, education, and curated Nostr content.",
+          "Discover Bitcoin meetups across Belgium. Real conversations, education, and a strong local community.",
         publisher: {
           "@type": "Organization",
           name: "Belgian Bitcoin Embassy",