Improved docs from XML generation_toolchain (#2103)

* Improved docs from XML generation_toolchain

- Make replaced-by a link
- Fix message field desc
- Make enums in param values into links
- Fixes following testing
- Add deprecated desc, if exists
- Add todo if we ever get WIP tags with text in them
- Make the main lists to dicts, to allow easier merging
- Merge XMLs
- Fix up ordering of items
- Make more robust - can spot new fields
- Improve table layout
- Add max, min, invalid, instance, default, to fields
- Add highlighting for WIP/Deprecated
- Minor fix to intros
- Add placeholder for building dialect tree
- Add summary of stuff in THIS file
- Flake8 Lint
- Workflow to deploy docs + dependencies file

* Update workflow to commit PR

.github/workflows/docs_build_and_deploy.yml

@@ -0,0 +1,69 @@
+name: Build markdown from XML and deploy
+
+on:
+  push:
+    branches: [ "master" ]
+  pull_request:
+    branches:
+      - '*'
+  workflow_dispatch: # Allows manual triggering
+
+# Sets permissions of the GITHUB_TOKEN to allow deployment to GitHub Pages
+permissions:
+  contents: read
+  pages: write
+  id-token: write
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v4
+      - name: Set up Python 3.10
+        uses: actions/setup-python@v5
+        with:
+          python-version: "3.10"
+
+      - name: Install dependencies
+        run: |
+          python -m pip install --upgrade pip
+          if [ -f doc/requirements.txt ]; then pip install -r doc/requirements.txt; fi
+
+      - name: Generate markdown from XML
+        run: |
+          cd doc
+          python3 mavlink_xml_to_markdown.py
+
+      - name: Upload docs artifact
+        uses: actions/upload-artifact@v4
+        with:
+          name: xml_file_markdown_docs
+          path: doc/messages/
+          retention-days: 1
+
+  deploy:
+    if: ${{ github.event_name == 'push' || (github.event_name == 'pull_request' && github.event.pull_request.merged) }}
+    needs: build
+    runs-on: ubuntu-latest
+
+    steps:
+    - name: Download Artifact
+      uses: actions/download-artifact@v4
+      with:
+        name: xml_file_markdown_docs
+        path: ~/_messages
+
+    # TBD - copy https://github.com/PX4/PX4-user_guide/blob/main/.github/workflows/docs_deploy.yml
+    - name: Deploy
+      run: |
+           git clone --single-branch --branch master https://${{ secrets.PX4BUILTBOT_PERSONAL_ACCESS_TOKEN }}@github.com/mavlink/mavlink-devguide.git
+           rm -rf mavlink-devguide/en/messages
+           mkdir -p mavlink-devguide/en/messages
+           cp -r ~/_messages/* mavlink-devguide/en/messages/
+           cd mavlink-devguide
+           git config --global user.name "${{ secrets.PX4BUILDBOT_USER }}"
+           git config --global user.email "${{ secrets.PX4BUILDBOT_EMAIL }}"
+           git add en/messages/*
+           git commit -a -m "MAVLink messages update `date`"
+           git push origin master