Polish workbench result states

frontend/src/styles/app.css

@@ -1070,7 +1070,8 @@ section th {
 .quality-check-card,
 .export-card,
 .latest-export-card,
-.empty-state {
+.empty-state,
+.result-state {
   border: 1px solid var(--line);
   border-radius: 8px;
   background: var(--panel-soft);
@@ -1114,11 +1115,56 @@ button.entity-card {
 .quality-check-card,
 .export-card,
 .latest-export-card,
-.empty-state {
+.empty-state,
+.result-state {
   min-width: 0;
   padding: 0.85rem;
 }
 
+.result-state {
+  display: grid;
+  gap: 0.18rem;
+  background: #ffffff;
+  overflow-wrap: anywhere;
+}
+
+.result-state strong {
+  font-size: 0.92rem;
+  line-height: 1.25;
+}
+
+.result-state p {
+  margin: 0;
+  color: var(--muted);
+  font-size: 0.84rem;
+  line-height: 1.38;
+}
+
+.result-state-error {
+  border-color: rgba(153, 27, 27, 0.25);
+  background: rgba(153, 27, 27, 0.07);
+}
+
+.result-state-error strong,
+.result-state-error p {
+  color: var(--danger);
+}
+
+.result-state-empty {
+  border-style: dashed;
+  background: var(--panel-soft);
+}
+
+.result-state-loading {
+  border-color: rgba(180, 83, 9, 0.24);
+  background: rgba(180, 83, 9, 0.08);
+}
+
+.result-state-ready {
+  border-color: rgba(15, 118, 110, 0.28);
+  background: var(--accent-soft);
+}
+
 .dataset-card,
 .model-card,
 .quality-check-card,