Function createFolder

apps/desktop/src/main/vault.ts:3358–3367

(
  root: string,
  topFolder: NoteFolder,
  subpath: string
)

 * and it just works).
 */
export async function createFolder(
  root: string,
  topFolder: NoteFolder,
  subpath: string
): Promise<void> {
  const trimmed = subpath.replace(/^\/+|\/+$/g, '')
  if (!trimmed) throw new Error('Folder name is required')
  const abs = resolveSafe(await folderRoot(root, topFolder), trimmed)
  await fs.mkdir(abs, { recursive: true })
}

/**
 * Rename or move a subfolder. `newSubpath` is the full target path