feat(docs): add architecture/roadmap (#9624)

* feat(docs): Add architecture overview

* add strucutre for rough roadmap

* add stable reference

* document stable links

* test mermaid again

* fix loading

* fix format to reduce warnings

* use local js

* add architecture ovierview

* add more sub-points

* more structure

* add general backend text

* add sme bqsic docs for frontend

* fix list syntax

* fix typo

docs/mkdocs.yml

@@ -91,6 +91,8 @@ nav:
         - Custom Barcodes: barcodes/custom.md
     - Development:
       - Contributing: develop/contributing.md
+      - Architecture: develop/architecture.md
+      - Roadmap: develop/roadmap.md
       - Devcontainer: develop/devcontainer.md
       - React Frontend: develop/react-frontend.md
     - Mobile App:
@@ -261,6 +263,9 @@ plugins:
       opening_tag: "{!"
       closing_tag: "!}"
   - search
+  - mermaid2:
+      # version: 11.6.0
+      javascript: javascripts/mermaid.min.js
   - git-revision-date-localized
   - mkdocs-simple-hooks:
       hooks:
@@ -286,6 +291,8 @@ plugins:
         'sref/contrib.md': 'develop/contributing.md'  #  https://github.com/inventree/InvenTree/blob/master/CONTRIBUTING.md.
         'sref/docs.md': 'index.md' #   https://docs.inventree.org/en/latest/
         'sref/api.md': 'api/index.md' #  https://demo.inventree.org/api-doc/
+        'sref/architecture.md': 'develop/architecture.md'
+        'sref/roadmap.md': 'develop/roadmap.md'
         'sref/code.md': 'https://github.com/inventree/InvenTree/tree/master' #  https://github.com/inventree/InvenTree/tree/master
         'sref/oci-image.md': 'https://hub.docker.com/r/inventree/inventree/tags' #  https://hub.docker.com/r/inventree/inventree/tags
         'sref/releases.md': 'https://github.com/inventree/InvenTree/releases' # https://github.com/inventree/InvenTree/releases
@@ -312,7 +319,7 @@ markdown_extensions:
       custom_fences:
         - name: mermaid
           class: mermaid
-          # format: !!python/name:pymdownx.superfences.fence_code_format
+          format: !!python/name:mermaid2.fence_mermaid_custom
   # - pymdownx.emoji:
   #     emoji_index: !!python/name:materialx.emoji.twemoji
   #     emoji_generator: !!python/name:materialx.emoji.to_svg