feat(motor antenna): amber at the order, not at the answer

The transmit gag starts when the move is commanded; the indicator waited
for a status poll to say the elements were travelling, so the two
disagreed by a second or more — and on an automatic follow (band change
with tracking on) there was no sign at all until a poll landed. The
backend now announces the order as it goes out, the interface shows it at
once and re-reads the antenna immediately, and the real status takes over
the moment it arrives.

The WSJT-X "grey out stations already worked" switch is renamed "Mark
stations already worked": with the colour now chosen by the operator the
old name described the wrong thing, but the switch still answers a
question the palette cannot — WHETHER dupes should be marked at all. On a
well-filled log they are most of a period, and a window where nearly
every line is coloured has stopped saying anything.

app.go

@@ -18313,7 +18313,22 @@ func motorBandAllowed(bands []string, hz int64) bool {
 // refreshed every couple of seconds — so a fresh command opens a short grace
 // window during which TX stays inhibited even before the poll confirms motion,
 // closing the gap at the start of a move.
-func (a *App) noteMotorMoveCommanded() { a.motorMoveCmdNs.Store(time.Now().UnixNano()) }
+// noteMotorMoveCommanded records — and ANNOUNCES — that the antenna has just
+// been told to move.
+//
+// The transmit gag already started here; the screen did not. It waited for a
+// status poll to come round and say the elements were travelling, so the
+// indicator turned orange a second or more after the button was pressed, and on
+// an automatic follow (band change with tracking on) the operator had no warning
+// at all until the poll landed. The event lets the interface show it at the
+// instant the order goes out, which is also when the transmitter is gagged —
+// one moment, one appearance.
+func (a *App) noteMotorMoveCommanded() {
+	a.motorMoveCmdNs.Store(time.Now().UnixNano())
+	if a.ctx != nil {
+		wruntime.EventsEmit(a.ctx, "motorant:move")
+	}
+}
 
 // applyMotorInhibit sets or clears the Flex transmit inhibit, but only when the
 // active CAT backend IS a FlexRadio — the inhibit is a Flex-API feature; with any