Fix contact form layout - wrap in grid column div

Header + form wrapped in .availability-right div so they stay
on the right side of the 2-column grid layout.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

index.html

@@ -242,6 +242,7 @@
                     <div id="check-result" class="check-result" style="display:none;"></div>
                 </div>
             </div>
+            <div class="availability-right">
                 <div class="availability-form-header">
                     <span class="overline">Yhteydenotto</span>
                     <h2>Ota yhteyttä</h2>
@@ -277,6 +278,7 @@
                 </form>
             </div>
         </div>
+    </div>
 </section>
 
 <!-- Footer -->