Restore native scrolling and reliable recognition; add feel tests

The previous round regressed the demo against main: dropped frames while
a finger drags, and swipes ignored when they start imperfectly.

Frame drops: hosts used touch-action: manipulation plus a blocking
touchmove listener, so Chrome waited for JavaScript on every touch move
(~30% of frames over 20ms in a drag, p95 28ms). Hosts again use per-axis
touch-action like main (pan-y for horizontal gestures, and so on), and
attach no touch listener.

Flaky recognition: an irreversible decision after 6px dropped swipes
with a wobbly or backward start. Recognition again measures from the
pointer-down point until the pointer lifts, as on main.

Scrolling beside gestures, natively:
- .from.scrollEdge() uses direction-specific touch-action while its
  scroller is at the edge (pan-x pan-down for drag-down at the top), the
  pull-to-refresh pattern from the Pointer Events spec. A passive scroll
  listener keeps it current; no touch handling blocks the browser.
- Where directional values are unsupported (Safari), scroll-edge
  gestures alone fall back to claiming touches at the browser's first
  cancelable touchmove.
- Hosts publish touch-action as --nvo-touch-action and the stylesheet
  applies it to descendants, so nested scroll containers keep it and
  horizontal swipes over lists are not cancelled. Ignored subtrees get
  touch-action: auto back.
- Bindings gain listeners and ref (spread on the host); the components
  use them.

Feel tests (npm run test:feel): Chromium with emulated touch checks
recognition on ten human-like traces, frame pacing budgets while
dragging (p95 <= 20ms, <= 5% over 20ms) for a swipe and a scroll-edge
dismiss, and the behaviour checks. Against the previous code they fail
on exactly the reported regressions; now 23/23 pass. On the demo, all
traces match main and drag frame pacing matches or beats it.

Commit thresholds are unchanged (0.25 distance, 0.2 flick).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Faarh2Ts6StJPcz2mRiHiR

packages/core-v2/verify/browser/app/main.ts

@@ -1,4 +1,5 @@
 import { createApp, defineComponent, h, ref } from "vue";
+import "../../../src/style.css";
 import {
   OriginGesture,
   OriginGestureSurface,