[docs] Zensical docs (#13253)

* add zensical workflow

* rebuild schema dynamically

* load in new module

* Use zensical for docs invoke tasks

* modern

* improved carousel layout

* Increased content width

* fix for app icons

* Ensure schema dir exists

* remove unused requirement

* update readthedocs process

* fix polar.sh link

* adjust link checker pattern

* Revert some of the original style

* remove legacy mkdocs requirements

* fix for ready.py

* reduce db warnings during schema generation

* Adjust padding

* fix index issues

* fix page title

* fix pages with broken or missing headers

* split data import API schema

* cleanup old carousel

* remove djlint link

.devcontainer/devcontainer.json

@@ -53,7 +53,7 @@
       "label": "InvenTree Server"
     },
     "8080": {
-      "label": "properdocs server"
+      "label": "Documentation server"
     }
   },