ui: Show call graphs, inheritance trees and include trees for active symbol (issue 249 337)

* Added TrailLayouter with Sugiyama dependency layouting
* Layouter supports horizontal and vertical layouts
* Added basic ui to graph view for showing incoming and outgoing paths
* Added depth slider, with infinity at maximum
* Disable trail ui when not available
* Added trail messages to undo stack and only use last one when undoing
* Added QtGraphLineBezier for trail graphs and refactored other line types
* Disabled edge activation for trail layouts, shown only visually
* Highlight all connected edges when hovering a node in trail layout
* Use different color when highlighting call edges for better contrast
* Fixed BucketLayouter issue when edge does not leave node
* Increased click area for angled edges

bug id = 249 337

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src/lib/CMakeLists.txt

@@ -12,6 +12,8 @@ add_files(
 	component/controller/helper/NetworkProtocolHelper.h
 	component/controller/helper/SnippetMerger.cpp
 	component/controller/helper/SnippetMerger.h
+	component/controller/helper/TrailLayouter.cpp
+	component/controller/helper/TrailLayouter.h
 
 	component/controller/ActivationController.cpp
 	component/controller/ActivationController.h
@@ -225,7 +227,7 @@ add_files(
 	data/TaskMergeStorages.h
 	data/TaskShowStatusDialog.cpp
 	data/TaskShowStatusDialog.h
-	
+
 	project/Project.cpp
 	project/Project.h
 	project/SourceGroupFactory.cpp
@@ -234,7 +236,7 @@ add_files(
 	project/SourceGroupFactoryModule.h
 	project/SourceGroup.cpp
 	project/SourceGroup.h
-	
+
 	settings/migration/Migration.cpp
 	settings/migration/Migration.h
 	settings/migration/MigrationDeleteKey.cpp
@@ -245,7 +247,7 @@ add_files(
 	settings/migration/MigrationMoveKey.h
 	settings/migration/SettingsMigrator.cpp
 	settings/migration/SettingsMigrator.h
-	
+
 	settings/ApplicationSettings.cpp
 	settings/ApplicationSettings.h
 	settings/ColorScheme.cpp
@@ -327,6 +329,7 @@ add_files(
 	utility/messaging/type/MessageActivateSourceLocations.h
 	utility/messaging/type/MessageActivateTokenIds.h
 	utility/messaging/type/MessageActivateTokens.h
+	utility/messaging/type/MessageActivateTrail.h
 	utility/messaging/type/MessageActivateWindow.h
 	utility/messaging/type/MessageChangeFileView.h
 	utility/messaging/type/MessageClearErrorCount.h