Normal (DEC 1000) and button-event (DEC 1002) tracking never report
motion without a pressed button, so hovering the canvas no longer
routes pointermove through the mouse reporting path unless any-event
tracking (DEC 1003) is enabled or the pointer was captured by a
reported press. Adds a Ghostty mode query for DEC 1003 and covers the
mode transitions in the vendored ABI regression test.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>