fix(elevation): drop the remembered hover when a new line is profiled

The flicker fix remembers the hovered sample index so a redraw can restore the
crosshair. A new profile is also a redraw, so loading a different line (e.g.
"Use selected", which does not go through _clearProfile) would paint a
crosshair and readout at the old index even though the pointer is on a button,
not the chart. Clear the hover when _profileLine installs a new line.

Author: giswqs

packages/plugins/src/plugins/elevation-profile/core/ElevationProfileControl.ts

@@ -405,6 +405,10 @@ export class ElevationProfileControl implements IControl, DeepLinkConsumer {
     embeddedElevations: number[] | null = null,
   ): Promise<void> {
     if (!this._map) return;
+    // A different line means the remembered hover index no longer refers to
+    // anything the pointer is on, so drop it before the new chart is drawn (a
+    // redraw restores the marker for whatever index is still set).
+    this._clearHover();
     this._state.line = coords.map((c) => [...c] as LngLat);
     this._state.elevations =
       embeddedElevations?.length === coords.length ? [...embeddedElevations] : null;