test(e2e): a plain member's shell is held end to end, and a page it cannot open lands on the feed

The suite ran only as an admin, so nothing end to end held what a member sees. A second seeded
account, a member with its own session, now walks every rail page (no admin entry, no admin call,
no error state) and follows links to the admin pages.

It found one: a member's link to an admin page showed the feed with no rail row current, and the
address bar kept naming the admin page — only the content fell back. The navigation state now
derives the page on screen through each module's gate (reachablePage), so the rail, the content,
the tab title and the address bar agree, on a link, a Back, and a role taken away mid-session.

frontend/playwright.config.ts

@@ -17,9 +17,10 @@ import { defineConfig, devices } from "@playwright/test";
 
 const BASE_URL = process.env.PW_BASE_URL || "http://127.0.0.1:8080";
 const STORAGE_STATE = "e2e/.auth/state.json";
-// The axe scan reads the DOM and the accessibility tree, which the engines build alike: one engine
-// answers for all, so the other projects leave it out instead of tripling its time.
-const CHROMIUM_ONLY = /a11y\.spec\.ts/;
+// The axe scan reads the DOM and the accessibility tree, which the engines build alike, and the
+// member spec checks which pages and requests a role gets, which no engine changes: one engine
+// answers for all, so the other projects leave them out instead of tripling their time.
+const CHROMIUM_ONLY = /(a11y|member)\.spec\.ts/;
 
 export default defineConfig({
   testDir: "./e2e",