feat(bx-mobile): display occur date on reimburse detail views

Always show the field and use an em dash when the date is empty.

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

bx-mobile/src/views/reimburse/ReimburseApprovePage.vue

@@ -249,6 +249,10 @@
                   <div class="adv-field__label">报销事由</div>
                   <div class="adv-field__value adv-field__value--multiline">{{ d.remark }}</div>
                 </div>
+                <div class="adv-field">
+                  <div class="adv-field__label">发生时间</div>
+                  <div class="adv-field__value">{{ d.occurDate || '—' }}</div>
+                </div>
               </div>
             </section>
 

bx-mobile/src/views/reimburse/ReimburseDetailPage.vue

@@ -114,6 +114,10 @@
                   <div class="adv-field__label">报销事由</div>
                   <div class="adv-field__value adv-field__value--multiline">{{ d.remark }}</div>
                 </div>
+                <div class="adv-field">
+                  <div class="adv-field__label">发生时间</div>
+                  <div class="adv-field__value">{{ d.occurDate || '—' }}</div>
+                </div>
               </div>
 
               <div class="adv-field reimburse-detail-total-row">