fix(meta,manifest): set default undefined for description and author

Author: valentinoli

Diff for: docs/content/en/manifest.md

@@ -27,7 +27,7 @@ pwa: {
 | --------------------------------- | --------------- | ------------------------------------------------------------ | --------------------------------------------------------------- |
 | `name` <sup>\*1</sup>             | `String`        | `package.json`'s name property                               | [maximum of 45 characters]                                      |
 | `short_name` <sup>\*1</sup>       | `String`        | `package.json`'s name property                               | [maximum of 12 characters]                                      |
-| `description` <sup>\*2</sup>      | `String`        | `package.json`'s description property                        |                                                                 |
+| `description` <sup>\*2</sup>      | `String`        | `undefined`                                                  |                                                                 |
 | `icons` <sup>\*1</sup>            | `Array<Object>` | `[]`                                                         | (See the [icon module])                                         |
 | `start_url` <sup>\*1</sup>        | `String`        | `routerBase + '?standalone=true'`                            | It has to be relative to where the manifest is placed           |
 | `display` <sup>\*1</sup>          | `String`        | `'standalone'`                                               |                                                                 |

Diff for: docs/content/en/meta.md

@@ -67,11 +67,11 @@ These articles will help you decide an appropriate value:
 - Meta: `title`
 
 ### `author`
-- Default: *npm_package_author_name*
+- Default: `undefined`
 - Meta: `author`
 
 ### `description`
-- Default: *npm_package_description*
+- Default: `undefined`
 - Meta: `description`
 
 ### `theme_color`

Diff for: src/manifest.ts

@@ -9,7 +9,7 @@ export function manifest (nuxt, pwa: PWAContext) {
   const defaults: ManifestOptions = {
     name: process.env.npm_package_name,
     short_name: process.env.npm_package_name,
-    description: process.env.npm_package_description,
+    description: undefined,
     publicPath,
     icons: [],
     start_url: routerBase + '?standalone=true',

Diff for: src/meta.ts

@@ -8,8 +8,8 @@ export function meta (nuxt, pwa: PWAContext, moduleContainer) {
   // Defaults
   const defaults: MetaOptions = {
     name: process.env.npm_package_name,
-    author: process.env.npm_package_author_name,
-    description: process.env.npm_package_description,
+    author: undefined,
+    description: undefined,
     charset: 'utf-8',
     viewport: undefined,
     mobileApp: true,

Diff for: types/manifest.d.ts

@@ -10,7 +10,7 @@ export interface ManifestOptions {
    */
   short_name: string,
   /**
-   * Default: _npm_package_description_
+   * Default: undefined
    */
   description: string,
   /**

Diff for: types/meta.d.ts

@@ -52,13 +52,13 @@ export interface MetaOptions extends Partial<ManifestOptions> {
    */
   title?: string,
   /**
-   * Default: _npm_package_author_name_
+   * Default: undefined
    *
    * Meta: `author`
    */
   author: string,
   /**
-   * Default: _npm_package_description_
+   * Default: undefined
    *
    * Meta: `description`
    */