ci: 👷 add workflow to autogenerate images from pumls (#145)

## Description 

So we don't have to do it manually (ever again 🌟 )

---------

Co-authored-by: Luke W. Johnston <lwjohnst86@users.noreply.github.com>

.github/workflows/puml-to-svg.yaml

@@ -0,0 +1,23 @@
+name: Generate SVG from PlantUML
+
+on:
+  pull_request:
+    paths:
+      - '**.puml'
+
+jobs:
+  generate-plantuml:
+    runs-on: ubuntu-latest
+    steps:
+    - name: checkout
+      uses: actions/checkout@v4
+      with:
+        fetch-depth: 1
+
+    - name: plantuml
+      id: plantuml
+      uses: grassedge/generate-plantuml-action@v1.5
+      with:
+        message: "chore: :bento: (re-)generate `.svg` from `.puml` files"
+      env:
+        GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}