test(e2e): cover the two guard-surface gaps found in the full-suite audit

Audit of all 12 e2e specs for the 'green-but-vacuous' class that broke
Grafana's SSO. The suite is otherwise sound (incident-driven, leakage-based);
two real coverage gaps surfaced:

- notebook.franksdank.cloud (open-notebook, deployed 2026-10-19) was a guarded
  vhost in NEITHER the 13-/14- GUARDED lists NOR any dedicated spec. A broken
  upstream would stay invisible - the exact 17-hermes class. Added to the 14-
  guard audit (unauth -> authentik gate, 'Open Notebook' leak marker) plus a
  new 21- that proves authenticated reachability to open-notebook's own login
  through the guard chain, with a positive app marker.
- prometheus.franksdank.cloud was only ever asserted '<500 and not a login
  wall' (13-/11-), which a 404 also passes. New 22- adds the app-is-really-
  there proof 20- gives Grafana: SSO handoff + its own /api/v1/status/buildinfo
  answers {status:success}.

Both specs wired into the standard project (playwright testMatch), which the
e2e_scaffold bats gate enforces. Verified live against the fleet; full bats
suite green.

tests/e2e/playwright.config.ts

@@ -31,8 +31,12 @@ export default defineConfig({
       // container name, so it needs its own pass condition). 18- joined on
       // 2026-09-24 (OpenWebUI SSO through authentik). 20- joined on 2026-10-21
       // (Grafana's OAuth2 relying-party login, which the edge-only 13- never
-      // follows).
-      testMatch: /(10|12|13|16|17|18|20)-.*\.spec\.ts/,
+      // follows). 21- joined 2026-10-21 (the open-notebook vhost, deployed
+      // 2026-10-19 - the newest guarded app, in neither GUARDED list nor any
+      // spec until now: the 17-hermes "uncovered vhost broke silently" class).
+      // 22- joins Prometheus's app-is-really-there proof (its own API), closing
+      // the "not a login wall but maybe a 404" hole 20- closed for Grafana.
+      testMatch: /(10|12|13|16|17|18|20|21|22)-.*\.spec\.ts/,
       use: { storageState: ".auth/qa-e2e.json" },
       dependencies: ["setup"],
     },

tests/e2e/specs/14-guard.spec.ts

@@ -15,7 +15,7 @@ const BASE = "https://www.franksdank.cloud";
 // Every vhost that Caddy routes through anubis:8923 (see dankclaw/Caddyfile).
 // Keep this list in lockstep with the Caddyfile: a new guarded vhost must be
 // added here or the guard-chain audit is incomplete.
-const GUARDED = ["www", "search", "romm", "files", "seerr", "grafana", "prometheus", "loki"];
+const GUARDED = ["www", "search", "romm", "files", "seerr", "grafana", "prometheus", "loki", "notebook"];
 
 // Markers that prove app content leaked past the guard to an anonymous user.
 const LEAK_MARKERS: Record<string, string[]> = {
@@ -25,6 +25,7 @@ const LEAK_MARKERS: Record<string, string[]> = {
   "seerr.franksdank.cloud": ["Request Movie"],
   "grafana.franksdank.cloud": ["Dashboards"],
   "prometheus.franksdank.cloud": ["Expression Browser", "Graph"],
+  "notebook.franksdank.cloud": ["Open Notebook"],
 };
 
 test("homepage root (/) is guarded for unauthenticated users", async ({ page }) => {

tests/e2e/specs/21-notebook.spec.ts

@@ -0,0 +1,52 @@
+import { expect, test } from "@playwright/test";
+
+// open-notebook (notebook.franksdank.cloud), deployed 2026-10-19, is a guarded
+// vhost whose outpost (notebook-proxy) fronts an app with its OWN password
+// login - the same shape as hermes (17-) and OpenWebUI (18-): the guard chain
+// (Anubis PoW -> authentik outpost) must hand off to the app, and the app's own
+// login page is the expected landing. Until now this host appeared in neither
+// the 13-/14- GUARDED lists nor any dedicated spec, so a broken upstream would
+// have stayed invisible - the exact 17-hermes "uncovered vhost" failure class.
+// 14- now covers the unauthenticated gate; this spec owns authenticated
+// reachability with a POSITIVE app marker, not just "not a login wall".
+
+const VHOST = "https://notebook.franksdank.cloud/";
+const CHALLENGE = "Making sure you're not a bot";
+
+test("notebook vhost reaches the open-notebook app through the guard chain", async ({ page }) => {
+  test.setTimeout(180_000);
+  await page.goto(VHOST);
+
+  // The Anubis proof-of-work clears in a real browser and the outpost hands off
+  // to the app; the user must never be parked on an authentik flow.
+  await expect
+    .poll(async () => !(await page.locator("body").innerText()).includes(CHALLENGE), { timeout: 90_000 })
+    .toBe(true);
+  await expect
+    .poll(() => new URL(page.url()).hostname, { timeout: 60_000 })
+    .toBe("notebook.franksdank.cloud");
+  expect(
+    new URL(page.url()).pathname.startsWith("/if/"),
+    "must not be parked on an authentik flow",
+  ).toBe(false);
+  expect(
+    await page.locator('input[name="uidField"]').count(),
+    "must not show the authentik login form",
+  ).toBe(0);
+
+  // Positive identity: the page really is open-notebook's own login, not a
+  // Caddy error or the IdP shell. The app answering its own login is the pass.
+  await expect(page, "destination title must be Open Notebook").toHaveTitle(/open notebook/i, {
+    timeout: 30_000,
+  });
+  await expect(page.locator("body"), "open-notebook login marker").toContainText(
+    /enter your password/i,
+    { timeout: 30_000 },
+  );
+  const body = await page.locator("body").innerText();
+  expect(body, "must not leak the IdP flow shell").not.toContain("Powered by authentik");
+  expect(body, "must not be a Caddy upstream error").not.toContain("Bad Gateway");
+
+  const resp = await page.request.get(VHOST);
+  expect(resp.status(), "open-notebook must answer, not error").toBeLessThan(500);
+});

tests/e2e/specs/22-prometheus-sso.spec.ts

@@ -0,0 +1,33 @@
+import { expect, test } from "@playwright/test";
+
+// Prometheus (prometheus.franksdank.cloud) sits behind the same embedded outpost
+// as Grafana. 13-sso and 11-admin only ever assert it is "not a login wall and
+// under 500" - which a Prometheus serving a 404 or a blank page would ALSO pass.
+// This is the app-is-really-there proof 20- provides for Grafana: with the
+// standard session the outpost hands off silently to the Prometheus UI, and the
+// app's own API answers success. A guard-route or upstream regression that lets
+// any non-Prometheus answer through fails here.
+
+test("SSO: Prometheus app answers its own API through authentik", async ({ page, request }) => {
+  test.setTimeout(180_000);
+  await page.goto("https://prometheus.franksdank.cloud/");
+
+  // Challenge clears, outpost hands off silently to the app (no credential prompt).
+  await expect
+    .poll(
+      async () => !(await page.locator("body").innerText()).includes("Making sure you're not a bot"),
+      { timeout: 90_000 },
+    )
+    .toBe(true);
+  await expect
+    .poll(() => new URL(page.url()).hostname, { timeout: 60_000 })
+    .toBe("prometheus.franksdank.cloud");
+  expect(await page.locator('input[name="uidField"]').count(), "no authentik form").toBe(0);
+  await expect(page, "must land on the Prometheus UI").toHaveTitle(/prometheus/i, { timeout: 30_000 });
+
+  // Load-bearing assertion: the Prometheus API itself answers, authenticated,
+  // through the outpost. An IdP bounce, a 404, or a raw upstream error fails here.
+  const api = await request.get("https://prometheus.franksdank.cloud/api/v1/status/buildinfo");
+  expect(api.status(), "Prometheus API must answer 200 through the guard").toBe(200);
+  expect((await api.json()).status, "Prometheus API must report success").toBe("success");
+});