refactor(companion): extract drawRowSelection() for the canonical list-row bar

Every drawList/AccordionList row opened with the same hand-written
display.drawSelectionRow(0, y-1, width-reserve, lineStep-1, sel) line —
14 copies of the same geometry and magic offsets. Add a drawRowSelection(d,
y, sel, reserve) helper in icons.h next to drawList and route the canonical
sites through it (Bot/LiveShare/Locator/Repeater/Settings/Tools/Nearby/
QuickMsg/Waypoints).

Rows that intentionally differ (full-width DashboardConfig/QuickMsg, the
keyboard/ringtone grids) keep their explicit drawSelectionRow() call — the
helper is opt-in rather than baked into drawList, so legitimate variants
aren't forced into one geometry. Framework doc updated to match.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

examples/companion_radio/ui-new/BotScreen.h

@@ -75,7 +75,7 @@ public:
                                     "Trigger Ch", "Reply Ch", "Commands",
                                     "Quiet from", "Quiet to" };
     drawList(display, ITEM_COUNT, _sel, _scroll, [&](int i, int y, bool sel, int reserve) {
-      display.drawSelectionRow(0, y - 1, display.width() - reserve, display.lineStep() - 1, sel);
+      drawRowSelection(display, y, sel, reserve);
       display.setCursor(2, y);
       display.print(labels[i]);
       display.setCursor(val_x, y);