fix: add missing memoryRerankerToggle style (light + dark mode)

The toggle button class was referenced in the TSX but not defined in the
Less file, causing it to render as a bare unstyled button. This commit
adds the style definition with hover/active states for both light and
dark mode.

Author: lecheng2018

console/src/pages/Agent/Config/index.module.less

@@ -806,6 +806,32 @@
   }
 }
 
+.memoryRerankerToggle {
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  width: 28px;
+  height: 28px;
+  margin-left: auto;
+  padding: 0;
+  border: none;
+  border-radius: 6px;
+  background: transparent;
+  color: rgba(20, 20, 19, 0.35);
+  cursor: pointer;
+  transition: background 0.2s, color 0.2s;
+  flex-shrink: 0;
+
+  &:hover {
+    background: rgba(20, 20, 19, 0.06);
+    color: rgba(20, 20, 19, 0.6);
+  }
+
+  &:active {
+    background: rgba(20, 20, 19, 0.1);
+  }
+}
+
 .memorySettingRow {
   display: flex;
   align-items: center;
@@ -1363,6 +1389,19 @@
     background: rgba(255, 255, 255, 0.035);
   }
 
+  .memoryRerankerToggle {
+    color: rgba(255, 255, 255, 0.35);
+
+    &:hover {
+      background: rgba(255, 255, 255, 0.08);
+      color: rgba(255, 255, 255, 0.6);
+    }
+
+    &:active {
+      background: rgba(255, 255, 255, 0.12);
+    }
+  }
+
   .memoryOverviewItem {
     border-right-color: rgba(255, 255, 255, 0.08);