fix(sftp): fix FileTree not visible — flex overflow layout issue

frontend/components/sftp/FileTree.vue

@@ -56,7 +56,7 @@ function formatSize(bytes: number): string {
 </script>
 
 <template>
-  <div class="flex-1 overflow-y-auto text-sm" @click="closeContext">
+  <div class="h-full overflow-y-auto text-sm" @click="closeContext">
     <div
       v-for="entry in entries"
       :key="entry.path"

frontend/components/sftp/SftpSidebar.vue

@@ -167,16 +167,16 @@ const breadcrumbs = computed(() => {
       </div>
 
       <!-- File tree area — either editor or directory listing -->
-      <template v-if="fileContent">
+      <div class="flex-1 min-h-0 overflow-hidden">
         <FileEditor
+          v-if="fileContent"
           :file-path="fileContent.path"
           :content="fileContent.content"
           @save="handleSave"
           @close="fileContent = null"
         />
-      </template>
-      <template v-else>
         <FileTree
+          v-else
           :entries="entries"
           :current-path="currentPath"
           @navigate="navigateTo"
@@ -185,7 +185,7 @@ const breadcrumbs = computed(() => {
           @delete="handleDelete"
           @rename="handleRename"
         />
-      </template>
+      </div>
     </div>
 
     <!-- Resize handle -->