Export explicitly the plugin options definition which is augmented (#11309)

Author: stockiNail

docs/developers/plugins.md

@@ -194,7 +194,7 @@ For example, to provide typings for the [`canvas backgroundColor plugin`](../con
 import {ChartType, Plugin} from 'chart.js';
 
 declare module 'chart.js' {
-  interface PluginOptionsByType<TType extends ChartType = ChartType> {
+  interface PluginOptionsByType<TType extends ChartType> {
     customCanvasBackgroundColor?: {
       color?: string
     }

src/types.ts

@@ -45,6 +45,10 @@ export {
   RadialLinearScale,
   TimeScale,
   TimeSeriesScale,
+  PluginOptionsByType,
+  ElementOptionsByType,
+  ChartDatasetProperties,
+  UpdateModeEnum,
   registerables
 } from './types/index.js';
 export * from './types/index.js';