[KM-591] [KM][FE] Highlight ingest button and show last ingested time for DB clients

- Show pulsing orange button when a DB has never been ingested to prompt user action
- Revert to muted style after first ingest, with relative timestamp ("5m ago", "2h ago") below the button
- Persist ingest timestamps per client in localStorage (km_ingest_timestamps)
- Fix incorrect toast message referencing non-existent chunks_ingested field; now shows table count from IngestResponse

src/app/components/KnowledgeManagement.tsx

@@ -93,6 +93,13 @@ export default function KnowledgeManagement({
   const [loadingDbTypes, setLoadingDbTypes] = useState(false);
   const [ingesting, setIngesting] = useState<string | null>(null);
   const [deletingClient, setDeletingClient] = useState<string | null>(null);
+  const [ingestTimestamps, setIngestTimestamps] = useState<Record<string, string>>(() => {
+    try {
+      return JSON.parse(localStorage.getItem("km_ingest_timestamps") ?? "{}");
+    } catch {
+      return {};
+    }
+  });
   const pollingTimers = useRef<Map<string, ReturnType<typeof setInterval>>>(new Map());
 
   // ── Data Catalog state ──────────────────────────────────────────────────────
@@ -307,7 +314,14 @@ export default function KnowledgeManagement({
     setIngesting(clientId);
     try {
       const res = await ingestDatabaseClient(clientId, userId);
-      toast.success(`Ingested ${res.chunks_ingested} chunks successfully`);
+      const tableCount = res.tables?.length ?? 0;
+      toast.success(`Ingested ${tableCount} table${tableCount !== 1 ? "s" : ""} successfully`);
+      const now = new Date().toISOString();
+      setIngestTimestamps((prev) => {
+        const updated = { ...prev, [clientId]: now };
+        localStorage.setItem("km_ingest_timestamps", JSON.stringify(updated));
+        return updated;
+      });
     } catch (err) {
       toast.error(err instanceof Error ? err.message : "Ingestion failed");
     } finally {
@@ -550,19 +564,39 @@ export default function KnowledgeManagement({
                           <p className="text-xs text-slate-400 capitalize">{client.db_type} · {client.status}</p>
                         </div>
                         <div className="flex items-center gap-1.5 flex-shrink-0">
-                          <button
-                            onClick={() => handleIngest(client.id)}
-                            disabled={ingesting === client.id || client.status === "inactive"}
-                            title="Ingest schema to knowledge base"
-                            className="flex items-center gap-1 text-xs px-2.5 py-1 rounded-lg bg-slate-100 hover:bg-orange-100 hover:text-[#FF8F00] text-slate-500 transition disabled:opacity-40 disabled:cursor-not-allowed"
-                          >
-                            {ingesting === client.id ? (
-                              <Loader2 className="w-3 h-3 animate-spin" />
-                            ) : (
-                              <Database className="w-3 h-3" />
+                          <div className="flex flex-col items-end gap-0.5">
+                            <button
+                              onClick={() => handleIngest(client.id)}
+                              disabled={ingesting === client.id || client.status === "inactive"}
+                              title={ingestTimestamps[client.id] ? `Last ingested: ${new Date(ingestTimestamps[client.id]).toLocaleString()}` : "Never ingested — click to ingest schema"}
+                              className={[
+                                "flex items-center gap-1 text-xs px-2.5 py-1 rounded-lg transition disabled:opacity-40 disabled:cursor-not-allowed",
+                                ingestTimestamps[client.id]
+                                  ? "bg-slate-100 hover:bg-orange-100 hover:text-[#FF8F00] text-slate-500"
+                                  : "bg-orange-500 hover:bg-orange-600 text-white shadow-sm shadow-orange-200 animate-pulse hover:animate-none",
+                              ].join(" ")}
+                            >
+                              {ingesting === client.id ? (
+                                <Loader2 className="w-3 h-3 animate-spin" />
+                              ) : (
+                                <Database className="w-3 h-3" />
+                              )}
+                              {ingesting === client.id ? "Ingesting…" : "Ingest"}
+                            </button>
+                            {ingestTimestamps[client.id] && (
+                              <span className="text-[10px] text-slate-300 leading-none">
+                                {(() => {
+                                  const diff = Date.now() - new Date(ingestTimestamps[client.id]).getTime();
+                                  const mins = Math.floor(diff / 60000);
+                                  if (mins < 1) return "just now";
+                                  if (mins < 60) return `${mins}m ago`;
+                                  const hrs = Math.floor(mins / 60);
+                                  if (hrs < 24) return `${hrs}h ago`;
+                                  return `${Math.floor(hrs / 24)}d ago`;
+                                })()}
+                              </span>
                             )}
-                            {ingesting === client.id ? "Ingesting…" : "Ingest"}
-                          </button>
+                          </div>
                           <button
                             onClick={() => handleDeleteClient(client.id)}
                             disabled={deletingClient === client.id}