The month grid sized its seven day columns from the width the launcher
reports, which is not the width the widget is drawn into. The columns came
out too wide, so only about four fitted and the last one was cut off.
Both widgets now draw at a WidgetSize the user picks in Settings, and
nothing reads LocalSize any more (SizeMode.Single for both). The month grid
lays its columns out at a fixed width and centres them, which also keeps a
multi-day event one connected bar; minResizeWidth is raised so the smallest
step always fits.
Closes#103Closes#51