Wire the CDP Input.dispatchMouseEvent "mouseMoved" type to a new
Frame.triggerMouseMove, which hit-tests the point via elementFromPoint
and dispatches mousemove, mouseover and mouseenter on the target,
mirroring the existing triggerMouseClick and the actions.zig hover()
event semantics.
Previously mouseMoved was silently ignored, so element.hover() over
Playwright/Puppeteer (CDP) fired no events. Addresses the hover gap
reported in #2043.