Add a synthetic quality suite and upstream parity record.

Assistant: grok
Assistant-Session: 01a1531b-6698-7732-8587-f28ea604bcdf

.forgejo/workflows/synthetic.yaml

@@ -0,0 +1,31 @@
+# Public synthetic suite. Do not fetch the OnCo corpus or its data license.
+name: synthetic
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+  workflow_dispatch:
+
+jobs:
+  suite:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+      - name: Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: "3.12"
+      - name: Node
+        uses: actions/setup-node@v4
+        with:
+          node-version: "22"
+      - name: Python dependencies
+        run: python3 -m pip install -r requirements.txt
+      - name: UI dependencies
+        working-directory: ui
+        run: npm ci
+      - name: Schema, ingest, UI, journeys, and notices
+        run: sh scripts/ci-synthetic.sh