GS_PH_VERSION command, per-printhead demo UI with --printheads CLI arg

Add getPhVersion(printheadId) to Xpl2Client with phVersionReceived signal
carrying all 8 response fields. Mock server echoes canned version data for
any requested printhead ID.

Demo app accepts --printheads N (default 10) to simulate N printheads.
The UI shows a scrollable per-PH list with individual and bulk version
query buttons, updating each row's version info on response.

1 files changed, 6 insertions, 0 deletions

diff --git a/demo/main.cpp b/demo/main.cpp
index 3100254..e0651d9 100644
--- a/demo/main.cpp
+++ b/demo/main.cpp
@@ -20,13 +20,19 @@ main (int argc, char *argv[])
 
   QCommandLineParser parser;
   parser.addOption ({ "wire-debug", "Log raw wire TX/RX to dev log" });
+  parser.addOption ({ "printheads",
+                      "Number of simulated printheads (default 10)", "N",
+                      "10" });
   parser.addHelpOption ();
   parser.process (app);
 
   if (parser.isSet ("wire-debug"))
     Xpl2Client::enableWireDebug ();
 
+  int phCount = qBound (1, parser.value ("printheads").toInt (), 99);
+
   QQmlApplicationEngine engine;
+  engine.setInitialProperties ({ { "demoPhCount", phCount } });
   QObject::connect (
       &engine, &QQmlApplicationEngine::objectCreationFailed, &app,
       [] () { QCoreApplication::exit (1); }, Qt::QueuedConnection);