fix(web): let Charcuterie own scroll memory, and delete ours

[Sawtaytoes]

What was wrong

Scroll a queue, follow a link, then press Back, and the queue started again at the top.

QueuePilot had two hand-rolled pieces fighting each other:

1. AppFrame scrolled main back to 0 on every route change, in a layout effect. That
   effect sits above the page, so it ran after any restore below it and overwrote it.
2. QueuesView kept a homeScroll module global. That version was one-way and one-route:
   it only worked coming back to Queues, and only when the queue had been opened by its
   title.

What changed

@charcuterie/ui@4.0.0 makes scroll memory automatic. Main remembers where each history
entry was scrolled to, re-applies it as the content arrives, and stops the moment the reader
scrolls. No browser does this for an inner scrollport, and Shell makes <main> this app's
one vertical scroll region.

• main.tsx wraps the app in <ReactRouterAdapter> inside <BrowserRouter>. One component
  now supplies both router seams: the link seam it already had, and the scroll entry.
• AppFrame loses its blanket reset. The library answers the same question better: a new
  path starts at the top, a search-param change is left alone, and a remembered entry is put
  back.
• QueuesView and state/ui.ts lose homeScroll.
• main.test.ts reads main.tsx as source and asserts the adapter is present and sits
  inside the router. A root wiring mistake has no unit-test surface otherwise.

Evidence

Driven against the synthetic e2e fixtures (e2e/fixtures/), never household data. Both
runs are identical up to the click: /q/bob in a 1400x600 window, list 977 px in a 506 px
scrollport, scrolled to the bottom at 471 px, out to Queues by the nav link, then Back.

	main	this branch
scrollTop before leaving	471	471
scrollTop after Back	0	471

The offset was sampled every 500 ms for eight seconds after Back. It held at 471 for all
sixteen samples.

Before leaving — both builds, identical

After Back — main starts the queue again at the top

After Back — this branch keeps the reader's place

The SHA-pinned image links are re-pinned to the squashed commit after the merge.

Gates

yarn typecheck, yarn test (23 + 29 files, 324 + 371 tests), biome check (0 errors,
74 pre-existing warnings), yarn build — all pass.