feat(admin): typed Radio/Routing field editors; pre-release audit fixes

Tools > Admin: split the Radio tab's single "f,bw,sf,cr" comma-string
field (free-text keyboard) into 4 independent, type-appropriate rows --
Frequency (same digit-cursor DigitEditor Settings/Repeater use locally),
Bandwidth/Spreading factor/Coding rate (discrete-set LEFT/RIGHT stepping),
plus TX power and the 3 Routing numeric fields as number steppers and
Repeat as an ON/OFF toggle. Edits happen locally (zero mesh traffic per
keystroke); only Enter sends one combined `set`, Cancel sends nothing.

Full pre-release audit of all 16 commits since v1.22 (5 parallel focus
areas: display/font, keyboard/messages, Nodes/Admin, Bot/channels,
UITask+NodePrefs schema) turned up and fixed:

- Admin: fetched FK_NUMBER values weren't clamped to the field's range,
  so a value already out-of-range could get stuck unreachable; fixed
  commit-time float format noise (%.6f -> %.3f); Cancel/failed-login
  always returned to the Nodes picker even when Admin was opened
  directly from a node's Hold-Enter action -- now returns to wherever
  it was actually opened from (AdminScreen::_from_picker).
- Keyboard: one-shot Shift was consumed after the *first* T9 multi-tap,
  so cycling to the 2nd/3rd candidate always came out lowercase --
  fixed by caching the cycle's caps state (t9_caps).
- Messages: history is numbered newest-first, so a message arriving
  while scrolled up to an older one silently relabeled the view onto a
  different message -- selection now shifts with the insert.
- Channels: onChannelRemoved() didn't clear ch_notif_override/
  ch_notif_muted/ch_fav_bitmask despite its own contract comment
  requiring it (now far more reachable via the on-device Delete);
  an all-zero hex secret silently self-deleted the channel it was
  just saved into (collides with the empty-slot sentinel) -- rejected.
- Room login: isRoomLoggedIn() indexed the login-tracking ring
  directly instead of via its head offset, silently wrong once the
  ring wraps (8+ rooms/session) -- the new on-device Logout depends
  on this being right.
- Font/display: removed the now fully-inert Settings > Display > Font
  toggle and the dead LemonFont.h (retired by the earlier misc-fixed
  font unification, zero remaining includes); fixed a copy-pasted
  "5x7" comment (font is 6x9), two meaningless dead ternaries, and an
  OLED/e-ink inconsistency in the undefined-glyph fallback box offset.
- AdminField's `kind`/bounds fields no longer rely on default member
  initializers inside aggregate-init: this toolchain's actual nRF52
  build (unlike env:native) has no explicit -std= override, so it
  predates C++14's aggregate-with-default-member-initializer rule.
  Given an explicit constructor instead -- portable regardless of
  standard, all existing field-table literals unchanged.

Docs updated to match: tools_screen.md (Diagnostics as a 3-tab
carousel, was documented as one flat screen), message_screen.md
(chat bubbles, newest-at-bottom, cursor mode, secret validation),
settings_screen.md (dropped the dead Font row), solo_ui_framework.md
(header menu_hint signatures, icon priority-drop, KeyboardWidget's
T9/alphabets/cursor-mode). release-notes.md gains the v1.23 section
covering all of the above plus the other 15 commits since v1.22.

Build-verified on WioTrackerL1_companion_solo_dual.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

examples/companion_radio/ui-new/ChannelsView.h

@@ -52,6 +52,14 @@ class ChannelsView {
         if (*end != 0) return false;
         tmp[i] = (uint8_t)v;
       }
+      // An all-zero 16-byte secret is the sentinel setChannelLocal() reads as
+      // "slot deleted" (see isAllZero() in MyMesh.cpp) -- saving one here would
+      // pass, then immediately trigger onChannelRemoved() on this very slot,
+      // silently discarding the channel and its bot/notif/favourite state.
+      // Reject it up front rather than let that self-delete happen invisibly.
+      bool all_zero = true;
+      for (int i = 0; i < 16 && all_zero; i++) if (tmp[i]) all_zero = false;
+      if (all_zero) return false;
       memset(out, 0, 32);
       memcpy(out, tmp, 16);
       return true;
@@ -68,7 +76,7 @@ class ChannelsView {
     if (_name[0] == '\0') { _task->showAlert("Name required", 1200); return; }
     uint8_t secret[32];
     if (!deriveSecret(secret)) {
-      _task->showAlert(_hex_mode ? "Need 32 hex chars" : "Secret required", 1400);
+      _task->showAlert(_hex_mode ? "Invalid secret" : "Secret required", 1400);
       return;
     }
     ChannelDetails ch;