Merge pull request 'feat(ui): Impressum/Datenschutz footer links' (#4) from feat/footer-legal-links into main

remote.arcg.at has the same Medieninhaber (ARCG) as the homepage, so link the
legal pages there: Impressum -> amateurradioclubgraz.at/imprint/, Datenschutz ->
amateurradioclubgraz.at/datenschutz/ (the homepage DSE now covers the remote
station processing).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

public/index.html

@@ -551,6 +551,12 @@
       </nav>
     </main>
 
+    <footer class="site-footer">
+      <a href="https://amateurradioclubgraz.at/imprint/" target="_blank" rel="noopener noreferrer">Impressum</a>
+      <span class="site-footer-sep" aria-hidden="true">·</span>
+      <a href="https://amateurradioclubgraz.at/datenschutz/" target="_blank" rel="noopener noreferrer">Datenschutz</a>
+    </footer>
+
     <script src="/app.js" defer></script>
   </body>
 </html>

public/styles.css

@@ -885,3 +885,24 @@ html[data-theme="light"] .message.domain-notice {
     display: grid;
   }
 }
+
+/* Legal footer links (Impressum / Datenschutz -> homepage) */
+.site-footer {
+  margin: 2rem auto 1.25rem;
+  padding: 1rem;
+  text-align: center;
+  font-size: 0.85rem;
+  opacity: 0.8;
+}
+.site-footer a {
+  color: inherit;
+  text-decoration: underline;
+}
+.site-footer a:hover,
+.site-footer a:focus-visible {
+  opacity: 1;
+}
+.site-footer-sep {
+  margin: 0 0.5rem;
+  opacity: 0.6;
+}