Add debug More/Clear/Upload tools for paintings and artist portraits.

Extends the debug panel on painting detail and artist bio with a 20-result search picker, local image upload, and clear-to-empty-frame workflow, plus API routes, artist checkup migration, and documentation.

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

client/src/components/PaintingDetail.css

@@ -499,6 +499,84 @@
   cursor: wait;
 }
 
+.debug-more-btn {
+  flex: 1;
+  padding: 8px 10px;
+  border: 1px solid rgba(201, 169, 110, 0.55);
+  border-radius: 6px;
+  background: rgba(201, 169, 110, 0.08);
+  color: #e8d5b5;
+  font-size: 12px;
+  font-weight: 600;
+  cursor: pointer;
+}
+
+.debug-more-btn:hover:not(:disabled) {
+  background: rgba(201, 169, 110, 0.2);
+  border-color: #c9a96e;
+}
+
+.debug-more-btn:disabled {
+  opacity: 0.6;
+  cursor: wait;
+}
+
+.debug-action-buttons-secondary {
+  margin-top: 0;
+}
+
+.debug-clear-btn,
+.debug-upload-btn {
+  flex: 1;
+  padding: 8px 10px;
+  border-radius: 6px;
+  font-size: 12px;
+  font-weight: 600;
+  cursor: pointer;
+}
+
+.debug-clear-btn {
+  border: 1px solid rgba(232, 120, 100, 0.55);
+  background: rgba(232, 120, 100, 0.1);
+  color: #e87864;
+}
+
+.debug-clear-btn:hover:not(:disabled) {
+  background: rgba(232, 120, 100, 0.2);
+  border-color: #e87864;
+}
+
+.debug-upload-btn {
+  border: 1px solid rgba(140, 190, 140, 0.55);
+  background: rgba(140, 190, 140, 0.1);
+  color: #8cbe8c;
+}
+
+.debug-upload-btn:hover:not(:disabled) {
+  background: rgba(140, 190, 140, 0.2);
+  border-color: #8cbe8c;
+}
+
+.debug-clear-btn:disabled,
+.debug-upload-btn:disabled {
+  opacity: 0.6;
+  cursor: wait;
+}
+
+.painting-frame-empty {
+  min-height: 280px;
+  cursor: default;
+}
+
+.painting-frame-empty:hover {
+  transform: none;
+  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.5), inset 0 0 0 2px #c9a96e;
+}
+
+.painting-frame-cleared {
+  background: transparent;
+}
+
 .debug-image-status {
   margin: 0;
   font-size: 10px;