add configurable club login domains in RMS software

public/index.html

@@ -407,6 +407,19 @@
             <button id="maintenanceDisableBtn" type="button" class="ghost-btn">Wartungsmodus deaktivieren</button>
           </div>
 
+          <hr class="separator" />
+          <div class="section-head">
+            <h3>Login Domains</h3>
+            <span class="pill">E-Mail Richtlinie</span>
+          </div>
+          <label class="field" style="margin-top: 0.6rem">
+            <span>Erlaubte Login-Domains (CSV oder Zeilenumbruch)</span>
+            <textarea id="loginDomainsInput" rows="3" placeholder="arcg.at, oevsv.at"></textarea>
+          </label>
+          <div class="actions">
+            <button id="saveLoginDomainsBtn" type="button" class="ghost-btn">Login Domains speichern</button>
+          </div>
+
         </article>
         </section>