feat: hierarchical notebooks (tree), remove all list view code, delete 22 unused files

- Add parentId to Notebook model (tree structure)
- Update sidebar to render parent/child notebooks with expand/collapse
- Add sub-notebook creation from parent notebook
- Remove 'list' from NotesViewMode type everywhere
- Delete 22 unused components, hooks, and UI files
- Wrap revalidatePath in try-catch to prevent save 500
- Update notebook API to support parentId in creation

memento-note/components/create-notebook-dialog.tsx

@@ -8,20 +8,29 @@ import { useNotebooks } from '@/context/notebooks-context'
 interface CreateNotebookDialogProps {
   open?: boolean
   onOpenChange?: (open: boolean) => void
+  parentNotebookId?: string | null
 }
 
-export function CreateNotebookDialog({ open, onOpenChange }: CreateNotebookDialogProps) {
+export function CreateNotebookDialog({ open, onOpenChange, parentNotebookId }: CreateNotebookDialogProps) {
   const { t } = useLanguage()
-  const { createNotebookOptimistic } = useNotebooks()
+  const { createNotebookOptimistic, notebooks } = useNotebooks()
   const [name, setName] = useState('')
+  const [selectedParentId, setSelectedParentId] = useState<string | null>(parentNotebookId ?? null)
   const [isSubmitting, setIsSubmitting] = useState(false)
 
+  const rootNotebooks = notebooks.filter(nb => !nb.parentId)
+
   const handleSubmit = async (e: React.FormEvent) => {
     e.preventDefault()
     if (!name.trim()) return
     setIsSubmitting(true)
     try {
-      await createNotebookOptimistic({ name: name.trim(), icon: 'folder', color: '#64748B' })
+      await createNotebookOptimistic({
+        name: name.trim(),
+        icon: 'folder',
+        color: '#64748B',
+        parentId: selectedParentId,
+      })
       setName('')
       onOpenChange?.(false)
     } catch (err) {
@@ -33,6 +42,7 @@ export function CreateNotebookDialog({ open, onOpenChange }: CreateNotebookDialo
 
   const handleClose = () => {
     setName('')
+    setSelectedParentId(parentNotebookId ?? null)
     onOpenChange?.(false)
   }
 
@@ -40,7 +50,6 @@ export function CreateNotebookDialog({ open, onOpenChange }: CreateNotebookDialo
     <AnimatePresence>
       {open && (
         <div className="fixed inset-0 z-50 flex items-center justify-center p-4">
-          {/* Backdrop */}
           <motion.div
             initial={{ opacity: 0 }}
             animate={{ opacity: 1 }}
@@ -49,7 +58,6 @@ export function CreateNotebookDialog({ open, onOpenChange }: CreateNotebookDialo
             className="absolute inset-0 bg-black/50 backdrop-blur-sm"
           />
 
-          {/* Card */}
           <motion.div
             initial={{ opacity: 0, scale: 0.92, y: 20 }}
             animate={{ opacity: 1, scale: 1, y: 0 }}
@@ -79,6 +87,24 @@ export function CreateNotebookDialog({ open, onOpenChange }: CreateNotebookDialo
                 />
               </div>
 
+              {!parentNotebookId && rootNotebooks.length > 0 && (
+                <div>
+                  <label className="block text-[11px] uppercase tracking-widest font-bold text-muted-foreground mb-2">
+                    {t('notebook.parentNotebook') || 'Carnet parent'}
+                  </label>
+                  <select
+                    value={selectedParentId || ''}
+                    onChange={(e) => setSelectedParentId(e.target.value || null)}
+                    className="w-full bg-white dark:bg-zinc-800 border border-black/12 dark:border-white/15 rounded-lg px-4 py-3 outline-none focus:border-foreground/40 transition-colors text-sm text-foreground"
+                  >
+                    <option value="">{t('notebook.noParent') || 'Aucun (racine)'}</option>
+                    {rootNotebooks.map(nb => (
+                      <option key={nb.id} value={nb.id}>{nb.name}</option>
+                    ))}
+                  </select>
+                </div>
+              )}
+
               <div className="flex gap-3 pt-2">
                 <button
                   type="button"