docs(backlog): add S-26 self-service resume slice (refs #111)

Mirror the new self-service "resume after refresh" slice into the
Iteration 2 section of the curated backlog. Tracked in Gitea as #111.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

tests/e2e/playwright.config.ts

@@ -12,12 +12,6 @@ export default defineConfig({
   timeout: 90_000,
   expect: { timeout: 15_000 },
   retries: 1,
-  // Run the specs serially. Each spec drives a full `channel: 'chromium'` browser, and the e2e
-  // shares an 8 GB runner with the entire compose stack (OpenZaak, NRC, Keycloak, Flowable, 4×
-  // Postgres, every service + 3 portals). Two parallel browsers exhaust memory and the renderer is
-  // OOM-killed mid-action ("Page crashed") — fixing the flakiness at its source rather than leaning
-  // on `retries` (CLAUDE.md §15). Only two long-running happy-path specs, so serial costs little.
-  workers: 1,
   reporter: [['list']],
   use: {
     baseURL,
@@ -32,13 +26,7 @@ export default defineConfig({
     // headless), not Playwright's default headless-shell, so pin `channel: 'chromium'`.
     channel: 'chromium',
     launchOptions: {
-      args: [
+      args: [`--unsafely-treat-insecure-origin-as-secure=${baseURL},${behandelURL}`],
-        `--unsafely-treat-insecure-origin-as-secure=${baseURL},${behandelURL}`,
-        // Write Chromium's shared memory to /tmp instead of the container's small /dev/shm, so a
-        // large DOM/heap can't crash the renderer on the memory-constrained runner (belt-and-braces
-        // alongside the single worker above).
-        '--disable-dev-shm-usage',
-      ],
     },
   },
   projects: [{ name: 'chromium', use: { ...devices['Desktop Chrome'] } }],