Add vanilla parity harness and harden server boundaries

.github/workflows/verify.yml

@@ -0,0 +1,31 @@
+name: verify
+
+on:
+  push:
+  pull_request:
+
+permissions:
+  contents: read
+
+jobs:
+  verify:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-go@v5
+        with:
+          go-version: '1.26.x'
+          cache: true
+      - run: go build ./...
+      - run: go vet ./...
+      - run: go test ./...
+
+  race:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-go@v5
+        with:
+          go-version: '1.26.x'
+          cache: true
+      - run: go test -race ./...