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- MessageStore::addFromPacket and addFromString, superseded by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/FSCommon.cpp

@@ -30,44 +30,6 @@ SPIClass SPI_HSPI(HSPI);
 
 #endif // HAS_SDCARD
 
-/**
- * @brief Copies a file from one location to another.
- *
- * @param from The path of the source file.
- * @param to The path of the destination file.
- * @return true if the file was successfully copied, false otherwise.
- */
-bool copyFile(const char *from, const char *to)
-{
-#ifdef FSCom
-    // take SPI Lock
-    concurrency::LockGuard g(spiLock);
-    unsigned char cbuffer[16];
-
-    File f1 = FSCom.open(from, FILE_O_READ);
-    if (!f1) {
-        LOG_ERROR("Failed to open source file %s", from);
-        return false;
-    }
-
-    File f2 = FSCom.open(to, FILE_O_WRITE);
-    if (!f2) {
-        LOG_ERROR("Failed to open destination file %s", to);
-        return false;
-    }
-
-    while (f1.available() > 0) {
-        byte i = f1.read(cbuffer, 16);
-        f2.write(cbuffer, i);
-    }
-
-    f2.flush();
-    f2.close();
-    f1.close();
-    return true;
-#endif
-}
-
 /**
  * Renames a file from pathFrom to pathTo.
  *