Turn statistics back on for a new game and fix low winning scores

Winning turned statistics off and nothing turned them back on, while
the Settings checkbox still showed them as on. Resetting points now
turns them back on if the win turned them off, and the checkbox shows
the current state when Settings is opened.

A winning score of 1 could never be won and with 2 the first point was
not announced as match point, because the first-point check ran first.
The winning score also could not be kept from going below 1.

tests/integration/test_stats_after_win.gd.uid

@@ -0,0 +1 @@
+uid://d20y2gtespbou