perf(angular): bundle size improvements for angular (#16966)

angular/scripts/rollup.config.js

@@ -0,0 +1,22 @@
+import resolve from 'rollup-plugin-node-resolve';
+
+export default {
+  input: 'dist/index.js',
+  output: {
+    file: 'dist/fesm5.js',
+    format: 'es'
+  },
+  external: (id) => {
+    // inline @ionic/core deps
+    if (id === '@ionic/core') {
+      return false;
+    }
+    // anything else is external
+    return !(id.startsWith('.') || id.startsWith('/'));
+  },
+  plugins: [
+    resolve({
+      module: true,
+    })
+  ]
+};