Add public curator notes and U-shaped hall wall hang.

Paintings get editable curator notes with brass plates in the 3D hall, and visit order now uses the far/end wall between left and right.

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

client/src/components/PaintingDetail.css

@@ -441,6 +441,115 @@
   font-style: italic;
 }
 
+.curator-notes-panel {
+  max-width: 700px;
+  width: 100%;
+  margin-top: 20px;
+  padding: 16px 18px;
+  background: rgba(201, 169, 110, 0.1);
+  border-radius: 6px;
+  border: 1px solid rgba(201, 169, 110, 0.28);
+}
+
+.curator-notes-header {
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  gap: 12px;
+  margin-bottom: 10px;
+}
+
+.curator-notes-panel h3 {
+  margin: 0;
+  font-family: Georgia, 'Times New Roman', serif;
+  font-size: 15px;
+  font-weight: 600;
+  color: #c9a96e;
+}
+
+.curator-notes-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;
+}
+
+.curator-notes-empty {
+  margin: 0;
+  font-size: 13px;
+  color: rgba(201, 169, 110, 0.55);
+  font-style: italic;
+}
+
+.curator-notes-edit-btn,
+.curator-notes-save-btn,
+.curator-notes-cancel-btn {
+  font-family: Georgia, 'Times New Roman', serif;
+  font-size: 13px;
+  padding: 4px 10px;
+  border-radius: 4px;
+  cursor: pointer;
+  border: 1px solid rgba(201, 169, 110, 0.45);
+  background: transparent;
+  color: #c9a96e;
+}
+
+.curator-notes-edit-btn:hover,
+.curator-notes-cancel-btn:hover {
+  background: rgba(201, 169, 110, 0.12);
+}
+
+.curator-notes-save-btn {
+  background: rgba(201, 169, 110, 0.2);
+  color: #e8d5b5;
+}
+
+.curator-notes-save-btn:hover:not(:disabled) {
+  background: rgba(201, 169, 110, 0.32);
+}
+
+.curator-notes-edit-btn:disabled,
+.curator-notes-save-btn:disabled,
+.curator-notes-cancel-btn:disabled {
+  opacity: 0.55;
+  cursor: not-allowed;
+}
+
+.curator-notes-textarea {
+  display: block;
+  width: 100%;
+  box-sizing: border-box;
+  margin: 0;
+  padding: 10px 12px;
+  border-radius: 4px;
+  border: 1px solid rgba(201, 169, 110, 0.35);
+  background: rgba(15, 15, 26, 0.55);
+  color: rgba(232, 213, 181, 0.95);
+  font-family: Georgia, 'Times New Roman', serif;
+  font-size: 14px;
+  line-height: 1.6;
+  resize: vertical;
+}
+
+.curator-notes-textarea:focus {
+  outline: none;
+  border-color: rgba(201, 169, 110, 0.7);
+}
+
+.curator-notes-actions {
+  display: flex;
+  gap: 8px;
+  margin-top: 10px;
+}
+
+.curator-notes-error {
+  margin: 8px 0 0;
+  font-size: 13px;
+  color: #e08a6a;
+}
+
 .painting-description {
   max-width: 700px;
   margin-top: 20px;