add rescan button

frontend/src/pages/SettingsPage.tsx

@@ -3,6 +3,7 @@ import { useQuery, useMutation, useQueryClient } from "@tanstack/react-query";
 import { api, type Library } from "../api/client";
 
 function LibraryRow({ lib, onRemove }: { lib: Library; onRemove: (id: number) => void }) {
+  const qc = useQueryClient();
   const { data } = useQuery({
     queryKey: ["scan-status", lib.id],
     queryFn: () => api.libraries.scanStatus(lib.id),
@@ -11,6 +12,11 @@ function LibraryRow({ lib, onRemove }: { lib: Library; onRemove: (id: number) =>
 
   const scanning = data?.scanning ?? false;
 
+  const rescanMutation = useMutation({
+    mutationFn: () => api.libraries.rescan(lib.id),
+    onSuccess: () => qc.invalidateQueries({ queryKey: ["scan-status", lib.id] }),
+  });
+
   return (
     <li style={{ display: "flex", justifyContent: "space-between", alignItems: "center", padding: "8px 0", borderBottom: "1px solid var(--border-subtle)" }}>
       <div>
@@ -22,13 +28,22 @@ function LibraryRow({ lib, onRemove }: { lib: Library; onRemove: (id: number) =>
         )}
         <div style={{ fontSize: 12, color: "var(--text-secondary)" }}>{lib.path}</div>
       </div>
-      <button
-        onClick={() => onRemove(lib.id)}
-        disabled={scanning}
-        style={{ color: scanning ? "var(--text-muted)" : "var(--danger)", background: "transparent", border: "none" }}
-      >
-        Remove
-      </button>
+      <div style={{ display: "flex", gap: 8 }}>
+        <button
+          onClick={() => rescanMutation.mutate()}
+          disabled={scanning}
+          style={{ color: scanning ? "var(--text-muted)" : "var(--accent)", background: "transparent", border: "none" }}
+        >
+          Rescan
+        </button>
+        <button
+          onClick={() => onRemove(lib.id)}
+          disabled={scanning}
+          style={{ color: scanning ? "var(--text-muted)" : "var(--danger)", background: "transparent", border: "none" }}
+        >
+          Remove
+        </button>
+      </div>
     </li>
   );
 }