fix(rig): LCXL3 OLED repaints only on bring-up — send 0x7F after every write

Eye-in-the-loop probe (lcxl3-probe-display, 2026-09-21) falsified the
'a field write needs no re-summon' assumption: bare set_text on a visible
target (0x35 AND 0x36) never reaches the glass. Every text path now ends
in configure_display(target, 0x7F): touch overlay, 2s home tick, zero-anim.
Plus: ~10 Hz rate gate with latest-value-wins pending flush (H2 ceiling
untested — conservative), and the at-rest overlay re-arms every 0.9s
indefinitely so DJF state/zero stops self-destructing after 1.2s.