test(browser): the exit code a dead run and a violated one actually leave

Drives the built binary against a page with nothing to tap and reads the
process status, then the same run through campaign to pin what lands in
runs.jsonl: exit_code 1 there is a detection the analysis drops as missing
data.

test/browser/testdata/nothing-to-tap/spec.ts

@@ -0,0 +1,9 @@
+import { always, extract, taps } from "@sanderling/spec";
+
+const banner = extract((s) => s.ax.find({ id: "banner" })?.text ?? "").named("banner");
+
+const bannerStays = always(() => banner.current === "nothing here answers a tap");
+
+export const properties = { bannerStays };
+
+export const actionsRoot = taps;