Redesign 3D gallery as single hall per artist with exit navigation.

Restore React client source, add hall-to-hall navigation via painting influences grouped by movement, and update documentation.

Co-authored-by: Cursor <cursoragent@cursor.com>

client/src/api/client.ts

@@ -0,0 +1,69 @@
+import type {
+  TimelineData,
+  YearBounds,
+  Artist,
+  ArtistDetail,
+  PaintingDetail,
+  ArtistNavigation,
+} from '../types';
+
+const API = '/api';
+
+async function fetchJson<T>(url: string): Promise<T> {
+  const res = await fetch(url);
+  if (!res.ok) throw new Error(`API error: ${res.status}`);
+  return res.json();
+}
+
+export function imageUrl(path: string | null | undefined): string {
+  if (!path) return '/placeholder-art.svg';
+  return `/images/${path}`;
+}
+
+/** Image for 3D gallery — local cached files only (API fetch is too slow for realtime 3D) */
+export function galleryImageUrl(painting: {
+  thumbnail_path?: string | null;
+  image_path?: string | null;
+}): string | null {
+  if (painting.thumbnail_path) return `/images/${painting.thumbnail_path}`;
+  if (painting.image_path) return `/images/${painting.image_path}`;
+  return null;
+}
+
+export function paintingImageUrl(painting: {
+  id: number;
+  image_path?: string | null;
+  thumbnail_path?: string | null;
+}): string {
+  if (painting.image_path) return `/images/${painting.image_path}`;
+  if (painting.thumbnail_path) return `/images/${painting.thumbnail_path}`;
+  return `/api/paintings/${painting.id}/image?size=full`;
+}
+
+export async function preloadArtistImages(artistId: number): Promise<{ fetched: number; total: number }> {
+  const res = await fetch(`${API}/artists/${artistId}/preload-images`, { method: 'POST' });
+  if (!res.ok) throw new Error('Preload failed');
+  return res.json();
+}
+
+export const api = {
+  getBounds: () => fetchJson<YearBounds>(`${API}/bounds`),
+
+  getTimeline: (start: number, end: number) =>
+    fetchJson<TimelineData>(`${API}/timeline?start=${start}&end=${end}`),
+
+  getArtists: (start?: number, end?: number, movementId?: number) => {
+    const params = new URLSearchParams();
+    if (start != null) params.set('start', String(start));
+    if (end != null) params.set('end', String(end));
+    if (movementId != null) params.set('movement_id', String(movementId));
+    return fetchJson<Artist[]>(`${API}/artists?${params}`);
+  },
+
+  getArtist: (id: number) => fetchJson<ArtistDetail>(`${API}/artists/${id}`),
+
+  getArtistNavigation: (id: number) =>
+    fetchJson<ArtistNavigation>(`${API}/artists/${id}/navigation`),
+
+  getPainting: (id: number) => fetchJson<PaintingDetail>(`${API}/paintings/${id}`),
+};