fix(ui): use scroll:'manual' in intercept to honor rmx-reset-scroll=false

[okxint]

rmx-reset-scroll="false" has no effect. Even though state.resetScroll is correctly parsed to false, the page still scrolls to the top on navigation.

Root cause: event.intercept() defaults to scroll: 'after-transition', which tells the browser to automatically scroll to the top after the handler promise resolves — regardless of any manual scroll calls inside the handler. The guard on state.resetScroll only suppresses the manual window.scrollTo(0, 0) call; the browser's built-in automatic scroll runs unconditionally.

Fix: Pass scroll: 'manual' to event.intercept(). This delegates all scroll responsibility to the handler, which already has the correct if (state.resetScroll && isNewEntry) guard in place.

event.intercept({
  scroll: 'manual',  // ← added
  async handler() {
    // ...
    if (state.resetScroll && isNewEntry) {
      window.scrollTo(0, 0)  // only fires when resetScroll is true
    }
  },
})

No other changes needed — the existing manual scroll logic was already correct; it just wasn't the only scroll source.

Fixes #11617