Add per-notebook icons and sync

src/lib/utils/notebook-icons.ts

@@ -0,0 +1,50 @@
+export const NOTEBOOK_ICON_OPTIONS = [
+  { id: 'book', label: 'Book' },
+  { id: 'folder', label: 'Folder' },
+  { id: 'briefcase', label: 'Work' },
+  { id: 'home', label: 'Home' },
+  { id: 'star', label: 'Star' },
+  { id: 'heart', label: 'Heart' },
+  { id: 'lightbulb', label: 'Ideas' },
+  { id: 'code', label: 'Code' },
+  { id: 'flask', label: 'Research' },
+  { id: 'graduation', label: 'Study' },
+  { id: 'calendar', label: 'Calendar' },
+  { id: 'tasks', label: 'Tasks' },
+  { id: 'archive', label: 'Archive' },
+  { id: 'globe', label: 'Globe' },
+  { id: 'plane', label: 'Travel' },
+  { id: 'palette', label: 'Creative' }
+] as const;
+
+export type NotebookIconId = (typeof NOTEBOOK_ICON_OPTIONS)[number]['id'];
+
+const BUILTIN_PREFIX = 'builtin:';
+const BUILTIN_IDS: Record<NotebookIconId, true> = {
+  book: true,
+  folder: true,
+  briefcase: true,
+  home: true,
+  star: true,
+  heart: true,
+  lightbulb: true,
+  code: true,
+  flask: true,
+  graduation: true,
+  calendar: true,
+  tasks: true,
+  archive: true,
+  globe: true,
+  plane: true,
+  palette: true
+};
+
+export function encodeBuiltinNotebookIcon(icon: NotebookIconId): string {
+  return `${BUILTIN_PREFIX}${icon}`;
+}
+
+export function decodeBuiltinNotebookIcon(value: string | null | undefined): NotebookIconId | null {
+  if (!value?.startsWith(BUILTIN_PREFIX)) return null;
+  const icon = value.slice(BUILTIN_PREFIX.length);
+  return Object.hasOwn(BUILTIN_IDS, icon) ? icon as NotebookIconId : null;
+}