Remove dead code (#11082)

Removed:
- MessageStore::addFromPacket and addFromString, superseded by
  tryAddFromPacket
- GeoCoord rangeRadiansToMeters, distanceTo, bearingTo
- Router::rawSend, declared virtual with no override and no caller
- ContentHandler handleHotspot, handleFs, handleAdminSettings,
  handleAdminSettingsApply, handleDeleteFsContent and their commented
  route registrations, plus the now unreachable htmlDeleteDir and the
  handleUpdateFs declaration that had no definition
- ContentHelper replaceAll
- OnScreenKeyboardModule popup chain: showPopup, clearPopup, drawPopup,
  drawPopupOverlay and their state, unreachable since the frame based UI
  was replaced by baseUI
- DebugRenderer drawDebugInfoTrampoline, drawDebugInfoSettingsTrampoline
  and the orphaned drawFrameSettings
- NodeListRenderer calculateMaxScroll, drawColumns and a stale extern
  haveGlyphs declaration with no definition
- UIRenderer::haveGlyphs, Screen::blink,
  NotificationRenderer::showKeyboardMessagePopupWithTitle,
  VirtualKeyboard::getInputText
- InkHUD touchNavLeft, touchNavRight, Applet::getActiveNodeCount,
  ThreadedMessageApplet::saveMessagesToFlash
- TwoButton::setHandlerUp, TwoButtonExtended setHandlerUp,
  setJoystickDownHandlers, setJoystickUpHandlers
- CannedMessageModule LaunchRepeatDestination, isCharInputAllowed,
  hasMessages
- TrafficManagementModule resetStats, recordRouterHopPreserved,
  saturatingIncrement
- UnitConversions::MetersPerSecondToMilesPerHour
- EncryptedStorage getSessionRemainingSeconds
- BMI270Sensor::writeRegisters, GPS::hasFlow, FSCommon copyFile,
  SerialConsole consolePrintf, buzz playLongPressLeadUp,
  memGet displayPercentHeapFree

src/modules/OnScreenKeyboardModule.h

@@ -25,11 +25,6 @@ class OnScreenKeyboardModule
     static bool processVirtualKeyboardInput(const InputEvent &event, VirtualKeyboard *keyboard);
     bool draw(OLEDDisplay *display);
 
-    void showPopup(const char *title, const char *content, uint32_t durationMs);
-    void clearPopup();
-    // Draw only the popup overlay (used when legacy virtualKeyboard draws the keyboard)
-    void drawPopupOverlay(OLEDDisplay *display);
-
   private:
     OnScreenKeyboardModule() = default;
     ~OnScreenKeyboardModule();
@@ -39,15 +34,8 @@ class OnScreenKeyboardModule
     void onSubmit(const std::string &text);
     void onCancel();
 
-    void drawPopup(OLEDDisplay *display);
-
     VirtualKeyboard *keyboard = nullptr;
     std::function<void(const std::string &)> callback;
-
-    char popupTitle[64] = {0};
-    char popupMessage[256] = {0};
-    uint32_t popupUntil = 0;
-    bool popupVisible = false;
 };
 
 } // namespace graphics