refactor(ui): align screens to the documented UI conventions

Audit pass against docs/design/solo_ui_framework.md, converging deviations:

- prev/next: replace hand-rolled (c == KEY_LEFT || c == KEY_PREV) with
  keyIsPrev()/keyIsNext() in QuickMsgScreen, RingtoneEditor, TrailScreen,
  FullscreenMsgView. Two were real rotary-encoder gaps, not just style:
  NearbyScreen's filter and WaypointsView's hemisphere toggle used raw
  KEY_LEFT/RIGHT with no encoder twin, so the encoder couldn't drive them.
- NearbyScreen's list right column used a manual setCursor(width -
  getTextWidth(...)) instead of the existing drawTextRightAlign() helper
  (which also UTF-8-translates) — now uses it, like Diagnostics/Repeater.
- RepeaterScreen hand-rolled the whole drawList skeleton (scroll clamp +
  reserve + row loop + indicator); collapsed onto drawList().

No D-pad behaviour change; more uniform encoder support. Net -19 lines.

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

examples/companion_radio/ui-new/FullscreenMsgView.h

@@ -156,8 +156,8 @@ struct FullscreenMsgView {
   Result handleInput(char c) {
     if (c == KEY_UP)          { if (scroll > 0) scroll--; return NONE; }
     if (c == KEY_DOWN)        { if (scroll < _max_scroll) scroll++; return NONE; }
-    if (c == KEY_LEFT)        return NEXT;
+    if (keyIsPrev(c))         return NEXT;   // page between messages (encoder too)
-    if (c == KEY_RIGHT)       return PREV;
+    if (keyIsNext(c))         return PREV;
     if (c == KEY_CONTEXT_MENU) return REPLY;
     if (c == KEY_ENTER || c == KEY_CANCEL) return CLOSE;
     return NONE;

examples/companion_radio/ui-new/NearbyScreen.h

@@ -715,8 +715,7 @@ public:
           if (e.dist_km >= 0.0f) geo::fmtDist(right, sizeof(right), e.dist_km, useImperial());
           else                   strncpy(right, "?GPS", sizeof(right));
         }
-        display.setCursor(display.width() - display.getTextWidth(right) - 2 - reserve, y);
+        display.drawTextRightAlign(display.width() - reserve - 2, y, right);
-        display.print(right);
       });
     }
 
@@ -779,8 +778,8 @@ public:
       _detail_refresh_ms = millis();
       return true;
     }
-    if (c == KEY_LEFT)  { _filter = (_filter + F_COUNT - 1) % F_COUNT; refresh(); return true; }
+    if (keyIsPrev(c)) { _filter = (_filter + F_COUNT - 1) % F_COUNT; refresh(); return true; }
-    if (c == KEY_RIGHT) { _filter = (_filter + 1) % F_COUNT;          refresh(); return true; }
+    if (keyIsNext(c)) { _filter = (_filter + 1) % F_COUNT;          refresh(); return true; }
     return false;
   }
 };

examples/companion_radio/ui-new/QuickMsgScreen.h

@@ -1518,8 +1518,8 @@ public:
         }
         // LEFT/RIGHT cycle Notif/Melody in-place (menu stays open).
         if (!_pin_picker_active && _num_contacts > 0) {
-          bool left  = (c == KEY_LEFT || c == KEY_PREV);
+          bool left  = keyIsPrev(c);
-          bool right = (c == KEY_RIGHT || c == KEY_NEXT);
+          bool right = keyIsNext(c);
           if (left || right) {
             static const char* NOTIF_LABELS[] = { "default", "OFF", "ON" };
             static const char* ML[]           = { "global", "M1", "M2" };
@@ -1674,8 +1674,8 @@ public:
       if (_ctx_menu.active) {
         // LEFT/RIGHT cycle Notif/Melody/Fav in-place (menu stays open).
         if (_num_channels > 0) {
-          bool left  = (c == KEY_LEFT || c == KEY_PREV);
+          bool left  = keyIsPrev(c);
-          bool right = (c == KEY_RIGHT || c == KEY_NEXT);
+          bool right = keyIsNext(c);
           if (left || right) {
             static const char* NOTIF_LABELS[] = { "default", "OFF", "ON" };
             static const char* ML[]           = { "global", "M1", "M2" };

examples/companion_radio/ui-new/RepeaterScreen.h

@@ -143,39 +143,21 @@ public:
     display.setColor(DisplayDriver::LIGHT);
     display.drawCenteredHeader("REPEATER");
 
-    const int item_h  = display.lineStep();
-    const int start_y = display.listStart();
-    int visible = display.listVisible(item_h);
-    if (visible < 1) visible = 1;
-
     // Config only — live forwarding stats live on Tools › Diagnostics.
-    int total = _item_count;
+    drawList(display, _item_count, _sel, _scroll, [&](int row, int y, bool sel, int reserve) {
-    if (_sel < _scroll)            _scroll = _sel;
-    if (_sel >= _scroll + visible) _scroll = _sel - visible + 1;
-    int max_scroll = total - visible;
-    if (max_scroll < 0) max_scroll = 0;
-    if (_scroll > max_scroll) _scroll = max_scroll;
-    if (_scroll < 0) _scroll = 0;
-
-    const int reserve = scrollIndicatorReserve(display, total, visible);
-    for (int i = 0; i < visible && (_scroll + i) < total; i++) {
-      int row = _scroll + i;
-      int y = start_y + i * item_h;
-      char val[16];
-      bool sel = (row == _sel);
       int item = _items[row];
-      display.drawSelectionRow(0, y - 1, display.width() - reserve, item_h - 1, sel);
+      display.drawSelectionRow(0, y - 1, display.width() - reserve, display.lineStep() - 1, sel);
       display.setCursor(2, y);
       display.print(itemLabel(item));
       if (item == IT_RFREQ && sel && _editor.active()) {
         _editor.render(display, display.valCol(), y);
       } else {
+        char val[16];
         itemValue(item, p, val, sizeof(val));
         display.drawTextRightAlign(display.width() - reserve - 2, y, val);
       }
       display.setColor(DisplayDriver::LIGHT);
-    }
+    });
-    drawScrollIndicator(display, start_y, visible * item_h, total, visible, _scroll);
     display.setColor(DisplayDriver::LIGHT);
     if (_picker.menu.active) _picker.menu.render(display);
     return (_picker.menu.active || _editor.active()) ? 50 : 500;

examples/companion_radio/ui-new/RingtoneEditorScreen.h

@@ -164,8 +164,8 @@ public:
   bool handleInput(char c) override {
     bool up    = (c == KEY_UP);
     bool down  = (c == KEY_DOWN);
-    bool left  = (c == KEY_LEFT  || c == KEY_PREV);
+    bool left  = keyIsPrev(c);
-    bool right = (c == KEY_RIGHT || c == KEY_NEXT);
+    bool right = keyIsNext(c);
     bool enter = (c == KEY_ENTER);
     bool menu_key = (c == KEY_CONTEXT_MENU);
     bool cancel   = (c == KEY_CANCEL);

examples/companion_radio/ui-new/TrailScreen.h

@@ -143,8 +143,8 @@ public:
     if (_action_menu.active) {
       // LEFT/RIGHT cycles the focused value — only meaningful in the Settings
       // submenu; the popup stays open so the user can keep tapping.
-      if (c == KEY_LEFT || c == KEY_RIGHT || c == KEY_PREV || c == KEY_NEXT) {
+      if (keyIsPrev(c) || keyIsNext(c)) {
-        int dir = (c == KEY_RIGHT || c == KEY_NEXT) ? 1 : -1;
+        int dir = keyIsNext(c) ? 1 : -1;
         int idx = _action_menu.selectedIndex();
         if (idx >= 0 && idx < _act_count && _menu_level == ML_SETTINGS)
           cycleSetting((ActionId)_act_map[idx], dir);
@@ -207,8 +207,8 @@ public:
     }
     if (c == KEY_CONTEXT_MENU) { openActionMenu(); return true; }
 
-    if (c == KEY_LEFT  || c == KEY_PREV) { _view = (uint8_t)((_view + V_COUNT - 1) % V_COUNT); return true; }
+    if (keyIsPrev(c)) { _view = (uint8_t)((_view + V_COUNT - 1) % V_COUNT); return true; }
-    if (c == KEY_RIGHT || c == KEY_NEXT) { _view = (uint8_t)((_view + 1) % V_COUNT);          return true; }
+    if (keyIsNext(c)) { _view = (uint8_t)((_view + 1) % V_COUNT);          return true; }
     if (_view == V_SUMMARY && c == KEY_UP) {
       _summary_scroll = (_summary_scroll > 0) ? _summary_scroll - 1 : _summary_max_scroll;
       return true;

examples/companion_radio/ui-new/WaypointsView.h

@@ -309,7 +309,7 @@ public:
       if (c == KEY_CANCEL) { _mode = OFF; return true; }
       if (c == KEY_UP)   { _add_sel = (_add_sel > 0) ? _add_sel - 1 : 3; return true; }
       if (c == KEY_DOWN) { _add_sel = (_add_sel < 3) ? _add_sel + 1 : 0; return true; }
-      if (c == KEY_LEFT || c == KEY_RIGHT) {
+      if (keyIsPrev(c) || keyIsNext(c)) {
         if      (_add_sel == 0) _add_lat_neg = !_add_lat_neg;   // N <-> S
         else if (_add_sel == 1) _add_lon_neg = !_add_lon_neg;   // E <-> W
         return true;