Fix email loading issues and improve performance

- Removed limit on cached emails - now loads ALL cached emails from MinIO
- Kept IMAP limit at 50 for reasonable performance
- Added loading indicator showing when emails are being fetched
- Fixed ES module import issue in email-utils.ts
- Improved user experience with visual feedback during loading

This ensures all email threads load completely while maintaining reasonable performance

components/ClientEmailSection.vue

@@ -75,8 +75,14 @@
         </div>
       </div>
 
+      <!-- Loading State -->
+      <div v-if="isRefreshing && emailThreads.length === 0 && threads.length === 0" class="text-center py-8">
+        <v-progress-circular indeterminate color="primary" :size="48" />
+        <div class="text-body-2 mt-3 text-grey">Loading email history...</div>
+      </div>
+      
       <!-- Email Thread List -->
-      <div v-if="emailThreads.length > 0 || threads.length > 0" class="email-threads">
+      <div v-else-if="emailThreads.length > 0 || threads.length > 0" class="email-threads">
         <div class="text-subtitle-1 mb-3 d-flex align-center">
           Email History
           <v-spacer />