feat: hierarchical notebook system - trash, selectors, breadcrumb, sidebar tree

- Schema: soft delete with trashedAt on Notebook model
- API: PATCH/GET notebooks support trashedAt filtering with cascade
- Sidebar: recursive tree rendering with collapse/expand, visual guides, hover actions
- HierarchicalNotebookSelector: portal-based dropdown with search, breadcrumbs, dropUp support
- AI chat: context selector with Toutes mes notes + notebook selector
- Agent detail: flat selects replaced with HierarchicalNotebookSelector
- Breadcrumb: notebook path display on home page
- Trash view: card grid with countdown, restore/permanent delete
- CSS: design tokens (ink, paper, blueprint, concrete, etc.)
- Types: parentId, trashedAt added to Notebook interface

memento-note/components/note-inline-editor.tsx

@@ -978,7 +978,7 @@ export function NoteInlineEditor({
             scheduleSave()
           } : undefined}
           lastActionApplied={previousContent !== null}
-          notebooks={notebooks.map(nb => ({ id: nb.id, name: nb.name }))}
+          notebooks={notebooks.map(nb => ({ id: nb.id, name: nb.name, parentId: nb.parentId, trashedAt: nb.trashedAt }))}
           diagramInsertFormat={noteType === 'richtext' ? 'html' : 'markdown'}
         />
       )}