fix(sidebar): eliminate full page reloads and fix notebook actions visibility

- Fix createNotebookOptimistic to call loadNotebooks() + triggerRefresh()
  after POST, so new notebooks appear immediately without page reload
- Remove window.location.reload() from delete-notebook-dialog (context
  already handles state refresh)
- Rewrite edit-notebook-dialog to use updateNotebook() from context
  instead of raw fetch + full page reload
- Fix NoteRefreshContext: remove refreshKey from useCallback deps to
  prevent unstable triggerRefresh callback cascade
- Fix notebook actions menu visibility: consolidate NotebookActions and
  expand button into single positioned container with proper z-index
- Add actions menu to active/selected notebook (was previously missing)
- Use proper Notebook type instead of any in sidebar components
- Increase button pr-20 to pr-24 to reserve space for actions
- Remove redundant router.refresh() from create-notebook-dialog

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

keep-notes/components/delete-notebook-dialog.tsx

@@ -26,7 +26,6 @@ export function DeleteNotebookDialog({ notebook, open, onOpenChange }: DeleteNot
     try {
       await deleteNotebook(notebook.id)
       onOpenChange(false)
-      window.location.reload()
     } catch (error) {
       // Error already handled in UI
     }