feat: add preload api

Author: imtaotao

packages/runtime/core/src/garfish.ts

@@ -22,7 +22,7 @@ import { interfaces } from './interface';
 import { fetchStaticResources } from './utils';
 import { GarfishHMRPlugin } from './plugins/fixHMR';
 import { GarfishOptionsLife } from './plugins/lifecycle';
-import { GarfishPreloadPlugin } from './plugins/preload';
+import { loadAppResource, GarfishPreloadPlugin } from './plugins/preload';
 import { defaultLoadComponentOptions, getDefaultOptions } from './config';
 
 export class Garfish implements interfaces.Garfish {
@@ -180,6 +180,15 @@ export class Garfish implements interfaces.Garfish {
     return this;
   }
 
+  preloadApp(name: string) {
+    const appInfo = this.appInfos[name];
+    assert(
+      appInfo && appInfo.entry,
+      `Can't preloadApp unexpected module "${name}".`,
+    );
+    loadAppResource(this.loader, appInfo);
+  }
+
   async loadApp(
     appName: string,
     options: Partial<interfaces.LoadAppOptions> | string,