ci: add throwaway repro diagnostic workflow

Signed-off-by: Aaron Cupp <mrcupp@mrcupp.com>

Author: IamMrCupp

.github/workflows/repro-diagnostic.yml

@@ -0,0 +1,79 @@
+name: Repro diagnostic (throwaway)
+
+on:
+  push:
+    branches: [ci/repro-diagnostic]
+  workflow_dispatch:
+
+jobs:
+  diag:
+    runs-on: ubuntu-24.04
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Install system dependencies
+        run: |
+          sudo apt-get update
+          sudo apt-get install -y --no-install-recommends \
+            imagemagick \
+            fonts-poppins \
+            libcairo2 \
+            libjpeg-turbo8
+
+      - name: Locate Poppins on the runner
+        run: |
+          echo "### Poppins location" >> "$GITHUB_STEP_SUMMARY"
+          echo '```' >> "$GITHUB_STEP_SUMMARY"
+          echo "brand.toml default path:" >> "$GITHUB_STEP_SUMMARY"
+          ls -la /usr/share/fonts/truetype/google-fonts/Poppins-Medium.ttf 2>&1 >> "$GITHUB_STEP_SUMMARY" || true
+          echo "fc-list poppins:" >> "$GITHUB_STEP_SUMMARY"
+          fc-list 2>/dev/null | grep -i poppins >> "$GITHUB_STEP_SUMMARY" || echo "(none)" >> "$GITHUB_STEP_SUMMARY"
+          echo "find poppins-medium:" >> "$GITHUB_STEP_SUMMARY"
+          find /usr/share/fonts -iname 'Poppins-Medium*' 2>/dev/null >> "$GITHUB_STEP_SUMMARY" || true
+          echo '```' >> "$GITHUB_STEP_SUMMARY"
+
+      - uses: actions/setup-python@v5
+        with:
+          python-version: "3.12"
+          cache: pip
+
+      - run: pip install -r requirements.txt
+
+      - name: make check (BRANDING.md sync)
+        run: make check
+
+      - name: Rebuild all assets into logos/
+        # Point at whatever Poppins the runner actually has, if the default path is absent.
+        run: |
+          if [ ! -f /usr/share/fonts/truetype/google-fonts/Poppins-Medium.ttf ]; then
+            cand=$(find /usr/share/fonts -iname 'Poppins-Medium*' 2>/dev/null | head -1)
+            if [ -n "$cand" ]; then echo "POPPINS_TTF=$cand" >> "$GITHUB_ENV"; fi
+          fi
+          make build
+
+      - name: Report reproduction status (vs committed bytes)
+        run: |
+          {
+            echo "### logos/ changes after rebuild"
+            echo "Changed files by type:"
+            for d in svg png favicon; do
+              n=$(git status --porcelain -- "logos/$d/" | wc -l | tr -d ' ')
+              echo "- $d: $n changed"
+            done
+            echo ""
+            echo '```'
+            git status --porcelain -- logos/ || true
+            echo '```'
+            echo ""
+            echo "Diffstat:"
+            echo '```'
+            git diff --stat -- logos/ || true
+            echo '```'
+          } >> "$GITHUB_STEP_SUMMARY"
+
+      - name: Upload rebuilt logos
+        uses: actions/upload-artifact@v4
+        with:
+          name: rebuilt-logos
+          path: logos/
+          retention-days: 3