Merge branch 'rljacob/docs/addgh-pages' (PR #5942)

Add infrastructure to build markdown-based documentation located in each components "docs" directory into a 
single web-page of documentation. Makes use of mkdocs-monorepo-plugin.

Also add a skeleton of documentation subdirs and markdown files for EAM, ELM and MOSART.

Also add a github action to build and deploy the documentation on e3sm-project.github.io/e3sm whenever master is 
updated. And an action to build the docs on every PR.

[BFB]

.github/workflows/e3sm-gh-pages.yml

@@ -0,0 +1,39 @@
+name: Build and deploy gh-pages branch with Mkdocs
+
+on:
+  # Runs every time master branch is updated
+  push:
+    branches: ["master"]
+  # Runs every time a PR is open against master
+  pull_request:
+    branches: ["master"]
+  workflow_dispatch:
+
+concurrency:
+  # Prevent 2+ copies of this workflow from running concurrently
+  group: e3sm-docs-action
+
+jobs:
+  Build-and-Deploy-docs:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          show-progress: false
+          fetch-depth: 0 # Needed, or else gh-pages won't be fetched, and push rejected
+          submodules: false # speeds up clone and not building anything in submodules
+      - name: Show action trigger
+        run: echo "= The job was automatically triggered by a ${{github.event_name}} event."
+      - name: Set up Python 3.10
+        uses: actions/[email protected]
+        with:
+          python-version: "3.10"
+      - name: Install python deps
+        run: python3 -m pip install mkdocs-material pymdown-extensions mkdocs-monorepo-plugin mdutils
+      # build every time (PR or push to master)
+      - name: Build
+        run: mkdocs build --strict --verbose
+      # deploy only when it is a push
+      - if: ${{ github.event_name == 'push' }}
+        name: Deploy
+        run: mkdocs gh-deploy

.gitignore

@@ -24,5 +24,8 @@ buildnmlc
 buildlibc
 buildlib_cmakec
 
+#the site directory
+site
+
 # Ignore emacs backup files
 *~