data: indexer processes

* TaskBuildIndex starts seperate indexer processes and communicates via shared memory
* indexer processes get restarted if they fail
* indexer processes are killed when the app closes or crashes
* added utility class SharedMemory to allocate and access shared memory, providing basic data structures
* added SharedMemoryGarbageCollector for keeping track of running instances and cleaning up shared memory in case of a crash
* show errors for source files that crashed during indexing
* added basic exception handling to task scheduling
* added option to turn off processes and use threads in preferences, but still use shared memory

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src/lib_gui/qt/view/QtDialogView.cpp

@@ -179,7 +179,7 @@ void QtDialogView::updateIndexingDialog(size_t fileCount, size_t totalFileCount,
 
 void QtDialogView::finishedIndexingDialog(
 	size_t indexedFileCount, size_t totalIndexedFileCount, size_t completedFileCount, size_t totalFileCount,
-	float time, ErrorCountInfo errorInfo)
+	float time, ErrorCountInfo errorInfo, bool interrupted)
 {
 	std::stringstream ss;
 	ss << "Finished indexing: ";
@@ -198,7 +198,7 @@ void QtDialogView::finishedIndexingDialog(
 			m_windowStack.clearWindows();
 
 			QtIndexingDialog* window = createWindow<QtIndexingDialog>();
-			window->setupReport(indexedFileCount, totalIndexedFileCount, completedFileCount, totalFileCount, time);
+			window->setupReport(indexedFileCount, totalIndexedFileCount, completedFileCount, totalFileCount, time, interrupted);
 			window->updateErrorCount(errorInfo.total, errorInfo.fatal);
 
 			setUIBlocked(false);
@@ -206,6 +206,17 @@ void QtDialogView::finishedIndexingDialog(
 	);
 }
 
+void QtDialogView::hideDialogs()
+{
+	m_onQtThread(
+		[=]()
+		{
+			m_windowStack.clearWindows();
+			setUIBlocked(false);
+		}
+	);
+}
+
 int QtDialogView::confirm(const std::string& message, const std::vector<std::string>& options)
 {
 	int result = -1;