Tests: keep every app test out of the user's standard folders

QetAppTest::run() moved settings, configuration and data into a
temporary folder, but QStandardPaths still pointed at the user's own.
Two things follow on a developer's machine:

- qet-assistant.json, live-mode token included, is rewritten by every
  app test as its editor opens.
- A .qetautosave file left in the user's data folder makes QETApp offer
  to restore it in a modal dialog at start. Offscreen nobody answers,
  so all six app tests hang until ctest times them out.

Test mode is now enabled first thing in run(). tst_assistantinfopaths
(#1513) did this in its own main(); it goes back to QET_APP_TEST_MAIN.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

tests/qttest/qetapptest.h

@@ -36,6 +36,7 @@
 #include <QApplication>
 #include <QCoreApplication>
 #include <QSettings>
+#include <QStandardPaths>
 #include <QTemporaryDir>
 #include <QtTest>
 
@@ -86,6 +87,11 @@ inline QAction *action(const QString &name)
 template <typename Test>
 int run(int argc, char **argv)
 {
+		//Some files are written to the standard folders whatever
+		//--data-dir says (qet-assistant.json, with the live-mode token, as
+		//the editor opens): test mode, before anything is written, keeps
+		//them away from the user's own
+	QStandardPaths::setTestModeEnabled(true);
 	QApplication app(argc, argv);
 	QCoreApplication::setOrganizationName("QElectroTech");
 	QCoreApplication::setApplicationName("QElectroTech");

tests/qttest/tst_assistantinfopaths.cpp

@@ -25,7 +25,6 @@
 #include <QJsonDocument>
 #include <QJsonObject>
 #include <QSignalBlocker>
-#include <QStandardPaths>
 
 /**
 	qet-assistant.json names the user and company collections, and the qet
@@ -88,13 +87,6 @@ private slots:
 	}
 };
 
-int main(int argc, char **argv)
-{
-		//AssistantInfo writes to the standard data folder, whatever
-		//--data-dir says, and QETApp writes it as its editor opens: test
-		//mode from the very start keeps the user's own file out of reach.
-	QStandardPaths::setTestModeEnabled(true);
-	return QetAppTest::run<tst_assistantinfopaths>(argc, argv);
-}
+QET_APP_TEST_MAIN(tst_assistantinfopaths)
 
 #include "tst_assistantinfopaths.moc"