feat(companion): on-device scope + repeater scope filtering; fix CAD, UTF-8 truncation, Public channel, Nodes list, keyboard cursor

- Settings > Radio > Scope: type a community/region name on-device (derives
  the shared key the same "#name" -> SHA256 way as DEFAULT_FLOOD_SCOPE_NAME),
  previously only settable from a connected app.
- Tools > Repeater > Scope only + Extra scopes: only relay flood traffic
  matching the device's own scope or a comma-separated list of additional
  scopes, without changing what scope the device's own messages send under.
  No-op while unconfigured.
- getCADEnabled()/getInterferenceThreshold() were hardcoded off on
  companion_radio; CAD now auto-enables whenever RX power-save (duty-cycle)
  is active, since the noise floor isn't kept fresh during duty-cycle sleep.
- Message truncation to fit the send frame could split a multi-byte UTF-8
  character in half; now stops at the last complete character.
- The default "Public" channel was unconditionally re-added at every boot
  before the saved channel list was loaded, so deleting it never stuck.
  Only seeded now on a genuinely fresh device (no channel file yet).
- Tools > Nodes read contacts from the wrong starting offset, landing on
  internally-reserved bookkeeping slots instead of real contacts -- showed
  as blank "Unknown" rows and silently dropped that many real contacts off
  the end of the list.
- resetContacts() only cleared the first few reserved slots, not the whole
  contact table, contrary to its own comment; only reachable today via
  private-key import, fixed to match stated intent regardless.
- Keyboard's multi-line text preview could render the cursor on an empty
  line below short typed text instead of right after it.

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

examples/companion_radio/ui-new/KeyboardWidget.h

@@ -577,10 +577,18 @@ struct KeyboardWidget {
     // ...and the byte offset that line starts at.
     int ps = 0;
     for (int n = first_line * cpl; n > 0 && ps < len; n--) ps += kbUtf8CharBytesAt(buf, ps, len);
+    bool cursor_drawn = false;   // draw it on exactly one line, even once the text itself runs out
     for (int pl = 0; pl < prev_lines; pl++) {
       int pe = ps;   // byte offset cpl codepoints further along (or end of text)
       for (int k = 0; k < cpl && pe < len; k++) pe += kbUtf8CharBytesAt(buf, pe, len);
-      bool cursor_here = (ps <= cursor_pos && (cursor_pos < pe || pl == prev_lines - 1));
+      // cursor_pos == len == pe is the common "typing at the end" case: that's
+      // this line's cursor only if THIS is where the text actually ends (pe ==
+      // len), not just whichever line happens to be the bottom of the preview
+      // area -- short text (fitting in fewer than prev_lines rows) would
+      // otherwise always show the cursor stranded on the last blank row
+      // instead of right after what was just typed.
+      bool cursor_here = !cursor_drawn && ps <= cursor_pos && (cursor_pos < pe || pe == len);
+      if (cursor_here) cursor_drawn = true;
       int line_end = (len < pe) ? len : pe;
       char linebuf[KB_PREVIEW_BYTES + 2];   // cpl codepoints + cursor '_' + NUL
       if (cursor_here) {

examples/companion_radio/ui-new/NearbyScreen.h

@@ -173,7 +173,16 @@ class NearbyScreen : public UIScreen {
     int nc = the_mesh.getNumContacts();
     for (int i = 0; i < nc && _count < MAX_NEARBY; i++) {
       ContactInfo ci;
-      if (!the_mesh.getContactByIdx(i, ci)) continue;
+      // getContactByIdx() indexes the RAW contact table, whose first
+      // MAX_ANON_CONTACTS slots are reserved for anon-request bookkeeping
+      // (see BaseChatMesh::resetContacts()/ContactsIterator) -- getNumContacts()
+      // already excludes them from the count, so real contact 0 lives at raw
+      // index MAX_ANON_CONTACTS, not 0. Reading from 0 pulled those reserved
+      // (blank, type=ADV_TYPE_NONE) slots into the list as bogus "Unknown"
+      // rows, and silently dropped the same number of real contacts off the
+      // end -- while never touching the anon slots themselves, so it always
+      // reproduced the same way regardless of the auto-add overwrite setting.
+      if (!the_mesh.getContactByIdx(i + MAX_ANON_CONTACTS, ci)) continue;
       if (!typeMatchesFilter(ci.type, ci.flags, true)) continue;
 
       Entry& e = _entries[_count++];
@@ -188,7 +197,7 @@ class NearbyScreen : public UIScreen {
                     ? geo::haversineKm(_own_lat, _own_lon, ci.gps_lat, ci.gps_lon)
                     : -1.0f;
       e.type        = ci.type;
-      e.contact_idx = i;
+      e.contact_idx = i + MAX_ANON_CONTACTS;   // raw index -- other lookups re-key off this directly
       e.lastmod     = ci.lastmod;
       e.is_known    = true;
       e.is_live     = false;

examples/companion_radio/ui-new/RepeaterScreen.h

@@ -35,9 +35,10 @@ class RepeaterScreen : public UIScreen {
   enum Item {
     IT_REPEATER, IT_NETWORK,
     IT_RPRESET, IT_RFREQ, IT_RSF, IT_RBW, IT_RCR,   // dedicated profile (Custom network)
-    IT_SKIP, IT_HOPS, IT_YIELD, IT_SNR, IT_SUPPRESS
+    IT_SKIP, IT_HOPS, IT_YIELD, IT_SNR, IT_SUPPRESS, IT_SCOPE, IT_SCOPE_EXTRA
   };
-  uint8_t _items[12];
+  uint8_t _items[14];
+  bool    _editing_scope;   // keyboard is entering/editing the extra scopes
   int     _item_count;
 
   RadioPresetPicker _picker;
@@ -66,6 +67,8 @@ class RepeaterScreen : public UIScreen {
       _items[_item_count++] = IT_YIELD;
       _items[_item_count++] = IT_SNR;
       _items[_item_count++] = IT_SUPPRESS;
+      _items[_item_count++] = IT_SCOPE;
+      _items[_item_count++] = IT_SCOPE_EXTRA;
     }
     if (_sel >= _item_count) _sel = _item_count - 1;
     if (_sel < 0) _sel = 0;
@@ -84,7 +87,9 @@ class RepeaterScreen : public UIScreen {
       case IT_HOPS:     return "Max hops";
       case IT_YIELD:    return "Yield";
       case IT_SNR:      return "Min SNR";
-      case IT_SUPPRESS: return "Suppress dup";
+      case IT_SUPPRESS:    return "Suppress dup";
+      case IT_SCOPE:       return "Scope only";
+      case IT_SCOPE_EXTRA: return "Extra scopes";
     }
     return "";
   }
@@ -113,6 +118,10 @@ class RepeaterScreen : public UIScreen {
         else strncpy(buf, "OFF", n);
         break;
       case IT_SUPPRESS: strncpy(buf, p->repeat_suppress_dup ? "ON" : "OFF", n); break;
+      case IT_SCOPE:    strncpy(buf, p->repeat_scope_only ? "ON" : "OFF", n); break;
+      case IT_SCOPE_EXTRA:
+        strncpy(buf, p->repeat_extra_scopes[0] ? p->repeat_extra_scopes : "(none)", n);
+        break;
       default: strncpy(buf, "", n); break;
     }
     buf[n - 1] = '\0';
@@ -126,16 +135,17 @@ class RepeaterScreen : public UIScreen {
   }
 
 public:
-  RepeaterScreen(UITask* task) : _task(task), _dirty(false), _sel(0), _scroll(0), _item_count(1) {}
+  RepeaterScreen(UITask* task) : _task(task), _dirty(false), _sel(0), _scroll(0), _item_count(1), _editing_scope(false) {}
 
   void onShow() override {
     _dirty = false; _sel = 0; _scroll = 0;
     _picker.menu.active = false; _editor.freq.active = false;
     _picker.saving = false; _picker.deleting = false;
+    _editing_scope = false;
   }
 
   int render(DisplayDriver& display) override {
-    if (_picker.saving) return _task->keyboard().render(display);
+    if (_picker.saving || _editing_scope) return _task->keyboard().render(display);
 
     NodePrefs* p = _task->getNodePrefs();
     buildItems(p);
@@ -181,6 +191,23 @@ public:
       return true;
     }
 
+    // Keyboard editing mode for the extra (relay-only) scopes
+    if (_editing_scope) {
+      auto res = _task->keyboard().handleInput(c);
+      if (res == KeyboardWidget::DONE) {
+        if (p) {
+          strncpy(p->repeat_extra_scopes, _task->keyboard().buf, sizeof(p->repeat_extra_scopes) - 1);
+          p->repeat_extra_scopes[sizeof(p->repeat_extra_scopes) - 1] = '\0';
+          the_mesh.rebuildRepeatScopes();
+          _dirty = true;
+        }
+        _editing_scope = false;
+      } else if (res == KeyboardWidget::CANCELLED) {
+        _editing_scope = false;
+      }
+      return true;
+    }
+
     // Modal overlays first.
     if (_picker.menu.active) {
       auto res = _picker.menu.handleInput(c);
@@ -279,6 +306,14 @@ public:
     if (item == IT_SUPPRESS && (left || right || enter)) {
       p->repeat_suppress_dup ^= 1; _dirty = true; return true;
     }
+    if (item == IT_SCOPE && (left || right || enter)) {
+      p->repeat_scope_only ^= 1; _dirty = true; return true;
+    }
+    if (item == IT_SCOPE_EXTRA && enter) {
+      _task->keyboard().begin(p->repeat_extra_scopes, (int)sizeof(p->repeat_extra_scopes) - 1);
+      _editing_scope = true;
+      return true;
+    }
     return false;
   }
 };

examples/companion_radio/ui-new/SettingsScreen.h

@@ -61,6 +61,7 @@ class SettingsScreen : public UIScreen {
     CUSTOM_FREQ, CUSTOM_SF, CUSTOM_BW, CUSTOM_CR,
     POWER_SAVE,
     TX_APC,
+    SCOPE_NAME,
     // System section
     SECTION_SYSTEM,
     DEVICE_NAME,
@@ -555,6 +556,11 @@ class SettingsScreen : public UIScreen {
       // Suppressed (and locked) while repeating — a repeater holds full TX power.
       if (p && p->client_repeat) display.print("--");
       else display.print((p && p->tx_apc) ? "ON" : "OFF");
+    } else if (item == SCOPE_NAME) {
+      display.print("Scope");
+      int vx = valCol(display);
+      display.drawTextEllipsized(vx, y, display.width() - vx - _reserve,
+                                  (p && p->default_scope_name[0]) ? p->default_scope_name : "(none)");
 #if AUTO_OFF_MILLIS > 0
     } else if (item == AUTO_OFF) {
       display.print("AutoOff");
@@ -678,6 +684,7 @@ class SettingsScreen : public UIScreen {
   // Keyboard state for editing message slots
   int            _edit_slot = -1;  // -1 = not editing, 0..9 = slot being edited
   bool           _edit_name = false;  // editing DEVICE_NAME via the keyboard
+  bool           _edit_scope = false; // editing SCOPE_NAME via the keyboard
   KeyboardWidget* _kb;
 
   // Radio preset picker — names are too long for the value column, so Enter on
@@ -701,6 +708,7 @@ public:
   void onShow() override {
     _dirty = false;
     _edit_name = false;
+    _edit_scope = false;
     resetList();
     _editor.freq.active = false;
   }
@@ -708,7 +716,7 @@ public:
   int render(DisplayDriver& display) override {
     display.setTextSize(1);
 
-    if (_edit_slot >= 0 || _edit_name || _picker.saving) {
+    if (_edit_slot >= 0 || _edit_name || _edit_scope || _picker.saving) {
       return _kb->render(display);
     }
 
@@ -771,6 +779,19 @@ public:
       return true;
     }
 
+    // Keyboard editing mode for the scope name
+    if (_edit_scope) {
+      auto res = _kb->handleInput(c);
+      if (res == KeyboardWidget::DONE) {
+        the_mesh.setPrimaryScope(_kb->buf);
+        _dirty = true;
+        _edit_scope = false;
+      } else if (res == KeyboardWidget::CANCELLED) {
+        _edit_scope = false;
+      }
+      return true;
+    }
+
     // Digit-by-digit Freq editor
     if (_editor.active()) {
       if (_editor.handleFreqInput(c) && p) { _task->applyRadioParams(); _dirty = true; }
@@ -966,6 +987,12 @@ public:
       _kb->clearPlaceholders();   // a device name is literal, not a message
       return true;
     }
+    if (_selected == SCOPE_NAME && p && enter) {
+      _edit_scope = true;
+      _kb->begin(p->default_scope_name, (int)sizeof(p->default_scope_name) - 1);
+      _kb->clearPlaceholders();   // a scope name is literal, not a message
+      return true;
+    }
     if (_selected == REBOOT && enter) {
       _task->savePrefsIfDirty(_dirty);   // don't lose pending edits across the restart
       _task->showAlert("Rebooting...", 800);