Add analytics

[Decipher]

Is your feature request related to a problem? Please describe.
As a content author I want analytics so I can tailor my content to my audience to provide a better experience.

Describe the solution you'd like

• Create gtag plugin: [RFC] Support Global Site Tag (gtag.js) and Google Analytics  nuxt-community/gtm-module#82 (comment)

Describe alternatives you've considered

Additional context