New Columns and columns visibility

frontend/src/config/pages/keywords.config.tsx

@@ -36,6 +36,7 @@ export interface ColumnConfig {
   align?: 'left' | 'center' | 'right';
   width?: string;
   render?: (value: any, row: any) => React.ReactNode;
+  defaultVisible?: boolean; // Whether column is visible by default (default: true)
 }
 
 // BulkActionConfig and RowActionConfig are now in table-actions.config.tsx
@@ -163,7 +164,8 @@ export const createKeywordsPageConfig = (
       },
       {
         ...clusterColumn,
-        sortable: false,
+        sortable: true,
+        sortField: 'cluster_id',
         render: (_value: string, row: Keyword) => row.cluster_name || '-',
       },
       {
@@ -264,6 +266,52 @@ export const createKeywordsPageConfig = (
         sortField: 'created_at',
         render: (value: string) => formatRelativeDate(value),
       },
+      // Optional columns - hidden by default
+      {
+        key: 'updated_at',
+        label: 'Updated',
+        sortable: true,
+        sortField: 'updated_at',
+        defaultVisible: false,
+        render: (value: string) => formatRelativeDate(value),
+      },
+      {
+        key: 'volume_override',
+        label: 'Volume Override',
+        sortable: true,
+        sortField: 'volume_override',
+        defaultVisible: false,
+        render: (value: number | null) => value ? value.toLocaleString() : '-',
+      },
+      {
+        key: 'difficulty_override',
+        label: 'Difficulty Override',
+        sortable: true,
+        sortField: 'difficulty_override',
+        defaultVisible: false,
+        align: 'center' as const,
+        render: (value: number | null) => {
+          if (value === null || value === undefined) return '-';
+          const difficultyNum = getDifficultyNumber(value);
+          return typeof difficultyNum === 'number' ? (
+            <Badge
+              color={
+                difficultyNum === 1 || difficultyNum === 2
+                  ? 'success'
+                  : difficultyNum === 3
+                  ? 'warning'
+                  : 'error'
+              }
+              variant={difficultyNum === 5 ? 'solid' : 'light'}
+              size="sm"
+            >
+              {difficultyNum}
+            </Badge>
+          ) : (
+            difficultyNum
+          );
+        },
+      },
     ],
     filters: [
       {