refactor(plugin-pwa): migrate package to TS (#5941)

packages/docusaurus-plugin-pwa/src/plugin-pwa.d.ts

@@ -0,0 +1,34 @@
+/**
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+declare module '@docusaurus/plugin-pwa' {
+  export type pwaHead = {
+    tagName: string;
+    href?: string;
+    content?: string;
+    [attributeName: string]: string | boolean;
+  };
+
+  export type PluginOptions = {
+    debug?: boolean;
+    offlineModeActivationStrategies;
+    injectManifestConfig;
+    reloadPopup;
+    pwaHead: pwaHead[];
+    swCustom;
+    swRegister;
+  };
+}
+
+declare module '@theme/PwaReloadPopup' {
+  export type PwaReloadPopupProps = {
+    readonly onReload: () => void;
+  };
+
+  const PwaReloadPopup: (props: PwaReloadPopupProps) => JSX.Element;
+  export default PwaReloadPopup;
+}