show icon cache size

app/lib/extensions/database_table_size.dart

@@ -0,0 +1,11 @@
+import 'package:drift/drift.dart';
+
+extension TableSIze on DatabaseConnectionUser {
+  SingleSelectable<double> tableSize(TableInfo table) {
+    return customSelect(
+      'SELECT SUM(pgsize) /(1024.0 * 1024.0)AS pgsize_mb FROM dbstat WHERE name = ?1',
+      variables: [Variable<String>(table.actualTableName)],
+      readsFrom: {table},
+    ).map((QueryRow row) => row.read<double>('pgsize_mb'));
+  }
+}