Add proxy downloads and bulk file operations

- Implement proxy download endpoint for better mobile Safari compatibility
- Add bulk selection with checkboxes in file browser
- Add bulk actions bar for downloading/deleting selected files
- Replace direct S3 downloads with server-proxied downloads
- Fix download issues on mobile devices by using proper link handling

pages/dashboard/file-browser.vue

@@ -63,14 +63,52 @@
       </v-col>
     </v-row>
 
+    <!-- Bulk Actions Bar (shown when items selected) -->
+    <v-row v-if="selectedItems.length > 0" class="mb-4">
+      <v-col>
+        <v-alert
+          type="info"
+          variant="tonal"
+          closable
+          @click:close="selectedItems = []"
+        >
+          <div class="d-flex align-center justify-space-between">
+            <span>{{ selectedItems.length }} item(s) selected</span>
+            <div>
+              <v-btn
+                color="primary"
+                variant="text"
+                @click="downloadSelected"
+                prepend-icon="mdi-download"
+                class="mr-2"
+              >
+                Download
+              </v-btn>
+              <v-btn
+                color="error"
+                variant="text"
+                @click="confirmDeleteSelected"
+                prepend-icon="mdi-delete"
+              >
+                Delete
+              </v-btn>
+            </div>
+          </div>
+        </v-alert>
+      </v-col>
+    </v-row>
+
     <!-- File List -->
     <v-card>
       <v-data-table
+        v-model="selectedItems"
         :headers="headers"
         :items="filteredFiles"
         :loading="loading"
         :items-per-page="25"
         class="elevation-0"
+        show-select
+        item-value="name"
       >
         <template v-slot:item.displayName="{ item }">
           <div 
@@ -295,6 +333,7 @@ const toast = useToast();
 // Data
 const files = ref<FileItem[]>([]);
 const filteredFiles = ref<FileItem[]>([]);
+const selectedItems = ref<string[]>([]);
 const searchQuery = ref('');
 const loading = ref(false);
 const uploading = ref(false);
@@ -460,19 +499,17 @@ const createNewFolder = async () => {
   }
 };
 
-// Download file
+// Download file (using proxy for Safari compatibility)
 const downloadFile = async (file: FileItem) => {
   downloadingFiles.value[file.name] = true;
   
   try {
-    const response = await $fetch('/api/files/download', {
-      params: { fileName: file.name },
-    });
+    // Use proxy download endpoint for better mobile compatibility
+    const proxyUrl = `/api/files/proxy-download?fileName=${encodeURIComponent(file.name)}`;
     
-    // For mobile Safari compatibility, use a link element
+    // Create a link element
     const link = document.createElement('a');
-    link.href = response.url;
-    link.target = '_blank';
+    link.href = proxyUrl;
     
     // Extract clean filename for download
     let filename = file.displayName;
@@ -481,16 +518,94 @@ const downloadFile = async (file: FileItem) => {
     }
     
     link.download = filename;
+    link.style.display = 'none';
     document.body.appendChild(link);
     link.click();
-    document.body.removeChild(link);
+    
+    // Clean up
+    setTimeout(() => {
+      document.body.removeChild(link);
+    }, 100);
   } catch (error) {
-    toast.error('Failed to generate download link');
+    toast.error('Failed to download file');
   } finally {
     downloadingFiles.value[file.name] = false;
   }
 };
 
+// Download selected files
+const downloadSelected = async () => {
+  const selectedFiles = files.value.filter(file => selectedItems.value.includes(file.name) && !file.isFolder);
+  
+  if (selectedFiles.length === 0) {
+    toast.warning('Please select files to download (folders cannot be downloaded)');
+    return;
+  }
+  
+  // Download files sequentially with a small delay
+  for (const file of selectedFiles) {
+    await downloadFile(file);
+    await new Promise(resolve => setTimeout(resolve, 500)); // Small delay between downloads
+  }
+  
+  selectedItems.value = [];
+};
+
+// Confirm delete selected
+const confirmDeleteSelected = () => {
+  const itemsToDelete = files.value.filter(file => selectedItems.value.includes(file.name));
+  
+  if (itemsToDelete.length === 0) return;
+  
+  const hasFolder = itemsToDelete.some(item => item.isFolder);
+  const message = hasFolder 
+    ? `Are you sure you want to delete ${itemsToDelete.length} item(s)? This includes folders with all their contents.`
+    : `Are you sure you want to delete ${itemsToDelete.length} file(s)?`;
+  
+  if (confirm(message)) {
+    deleteSelected();
+  }
+};
+
+// Delete selected items
+const deleteSelected = async () => {
+  const itemsToDelete = files.value.filter(file => selectedItems.value.includes(file.name));
+  
+  deleting.value = true;
+  let successCount = 0;
+  let errorCount = 0;
+  
+  try {
+    for (const item of itemsToDelete) {
+      try {
+        await $fetch('/api/files/delete', {
+          method: 'POST',
+          body: { 
+            fileName: item.name,
+            isFolder: item.isFolder,
+          },
+        });
+        successCount++;
+      } catch (error) {
+        errorCount++;
+      }
+    }
+    
+    if (successCount > 0 && errorCount === 0) {
+      toast.success(`${successCount} item(s) deleted successfully`);
+    } else if (successCount > 0 && errorCount > 0) {
+      toast.warning(`${successCount} item(s) deleted, ${errorCount} failed`);
+    } else {
+      toast.error('Failed to delete items');
+    }
+    
+    selectedItems.value = [];
+    await loadFiles();
+  } finally {
+    deleting.value = false;
+  }
+};
+
 // Confirm delete
 const confirmDelete = (file: FileItem) => {
   fileToDelete.value = file;