Add guided tours and unify left-to-right hall wall hang.

Visitors walk published tours in a 3D hall with stop notes; curators edit drafts via Tour editor. All galleries (artist, movement, tour) place the first work left of the entrance view and the last on the right.

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

client/src/components/PaintingDetail.css

@@ -407,6 +407,40 @@
   display: block;
 }
 
+.tour-stop-panel {
+  max-width: 700px;
+  width: 100%;
+  margin-top: 20px;
+  padding: 16px 18px;
+  background: rgba(201, 169, 110, 0.12);
+  border-radius: 6px;
+  border: 1px solid rgba(201, 169, 110, 0.35);
+}
+
+.tour-stop-panel h3 {
+  margin: 0 0 10px;
+  font-family: Georgia, 'Times New Roman', serif;
+  font-size: 15px;
+  font-weight: 600;
+  color: #c9a96e;
+}
+
+.tour-stop-body {
+  margin: 0;
+  font-family: Georgia, 'Times New Roman', serif;
+  font-size: 14px;
+  line-height: 1.7;
+  color: rgba(232, 213, 181, 0.92);
+  white-space: pre-wrap;
+}
+
+.tour-stop-empty {
+  margin: 0;
+  font-size: 13px;
+  color: rgba(201, 169, 110, 0.55);
+  font-style: italic;
+}
+
 .painting-description {
   max-width: 700px;
   margin-top: 20px;