feat: Making Quartz available offline by making it a PWA (#465)

* Adding PWA and chaching for offline aviability

* renamed workbox config to fit Quartz' scheme

* Documenting new configuration

* Added missig umami documentation

* Fixed formatting so the build passes, thank you prettier :)

* specified caching strategies to improve performance

* formatting...

* fixing "404 manifest.json not found" on subdirectories by adding a / to manifestpath

* turning it into a plugin

* Removed Workbox-cli and updated @types/node

* Added Serviceworkercode to offline.ts

* formatting

* Removing workbox from docs

* applied suggestions

* Removed path.join for sw path

Co-authored-by: Jacky Zhao <j.zhao2k19@gmail.com>

* Removed path.join for manifest path

Co-authored-by: Jacky Zhao <j.zhao2k19@gmail.com>

* Removing path module import

* Added absolute path to manifests start_url and manifest "import" using baseUrl

* Adding protocol to baseurl

Co-authored-by: Jacky Zhao <j.zhao2k19@gmail.com>

* Adding protocol to start_url too then

* formatting...

* Adding fallback page

* Documenting offline plugin

* formatting...

* merge suggestion

Co-authored-by: Jacky Zhao <j.zhao2k19@gmail.com>

* merge suggestion

Co-authored-by: Jacky Zhao <j.zhao2k19@gmail.com>

* merge suggestion

Co-authored-by: Jacky Zhao <j.zhao2k19@gmail.com>

* merge suggestion

Co-authored-by: Jacky Zhao <j.zhao2k19@gmail.com>

* merge suggestion

Co-authored-by: Jacky Zhao <j.zhao2k19@gmail.com>

* merge suggestion

Co-authored-by: Jacky Zhao <j.zhao2k19@gmail.com>

* merge suggestion

Co-authored-by: Jacky Zhao <j.zhao2k19@gmail.com>

* merge suggestion

Co-authored-by: Jacky Zhao <j.zhao2k19@gmail.com>

* merge suggestion

Co-authored-by: Jacky Zhao <j.zhao2k19@gmail.com>

* merge suggestion

Co-authored-by: Jacky Zhao <j.zhao2k19@gmail.com>

* merge suggestion

Co-authored-by: Jacky Zhao <j.zhao2k19@gmail.com>

* merge suggestion

Co-authored-by: Jacky Zhao <j.zhao2k19@gmail.com>

* formatting...

* Fixing manifest path, all these nits hiding the actual issues .-.

* Offline fallback page through plugins, most things taken from 404 Plugin

* adding Offline Plugin to config

* formatting...

* Turned offline off as default and removed offline.md

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Co-authored-by: Jacky Zhao <j.zhao2k19@gmail.com>

quartz/cfg.ts

@@ -19,6 +19,7 @@ export type Analytics =
 
 export interface GlobalConfiguration {
   pageTitle: string
+  description: string
   /** Whether to enable single-page-app style rendering. this prevents flashes of unstyled content and improves smoothness of Quartz */
   enableSPA: boolean
   /** Whether to display Wikipedia-style popovers when hovering over links */