fix: reset hovered state on ESC

[saintmatthieu]

Needed for audacity/audacity#10223

Without this, ESC doesn't clear the point after click-to-create-point and dragging. The point would then only disappear after the mouse is released and moved:

Screencast.from.2026-05-15.14-25-09.webm

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Build configuration

audacity: audacity/audacity/master
audacity platforms: linux_x64
musescore: musescore/MuseScore/master
musescore platforms: linux_x64