feat(test): M5.3 — Playwright e2e harness for the dev stack

playwright.config.ts + tests/e2e/{apex,tenant,health}.spec.ts. make e2e for local. CI e2e job opt-in via RUN_E2E repo variable. OIDC click-through deferred to when stage is up.

Refs: M5.3

tests/e2e/health.spec.ts

@@ -0,0 +1,32 @@
+import { expect, test } from "@playwright/test";
+
+// Health checks — confirm the underlying services are reachable before the
+// stack-dependent tests run. Skips with a clear reason if anything is down,
+// so we don't waste 30s on a slow OIDC redirect when Keycloak isn't running.
+
+test.describe("dev stack health @needs-stack", () => {
+  test("portal /api/auth/providers responds", async ({ request }) => {
+    const r = await request.get("/api/auth/providers");
+    expect(r.status()).toBe(200);
+    const data = await r.json();
+    expect(data).toHaveProperty("keycloak");
+  });
+
+  test("tenant-registry /healthz responds", async ({ request }) => {
+    const url =
+      process.env.PLAYWRIGHT_TENANT_REGISTRY_URL ?? "http://localhost:8090";
+    const r = await request.get(`${url}/healthz`);
+    expect(r.status()).toBe(200);
+    expect(await r.json()).toMatchObject({ status: "ok" });
+  });
+
+  test("keycloak realm metadata is exposed", async ({ request }) => {
+    const url =
+      process.env.PLAYWRIGHT_KEYCLOAK_URL ??
+      "http://localhost:8080/realms/breakpilot-dev";
+    const r = await request.get(`${url}/.well-known/openid-configuration`);
+    expect(r.status()).toBe(200);
+    const cfg = await r.json();
+    expect(cfg.issuer).toContain("breakpilot-dev");
+  });
+});