fix: Default view dropdown settings — 5 vues + style + persistence

- Select remplacé: class sort-select (mal stylé) → settings-select (adapté)
- 5 vues: Tree, List, Details, Cards, Content (plus seulement 3)
- x-model="defaultView" + @change="saveDefaultView()"
- Sauvegarde localStorage 'fd_default_view'
- workspace page lit localStorage pour viewMode initial
- Settings → Default view persiste entre sessions et s'applique au workspace

app/templates/local_workspace.html

@@ -900,7 +900,7 @@ document.addEventListener('alpine:init', function() {
 
     // Sort
     sortBy: '',
-    viewMode: 'tree',
+    viewMode: localStorage.getItem('fd_default_view') || 'tree',
     viewMenuOpen: false,
     viewIcons: {tree:'🌳',list:'📋',details:'📊',title:'🏷️',content:'📝'},
     viewLabels: {tree:'Tree',list:'List',details:'Details',title:'Cards',content:'Content'},