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/data/access/StorageAccessProxy.cpp

@@ -184,6 +184,16 @@ std::shared_ptr<Graph> StorageAccessProxy::getGraphForActiveTokenIds(const std::
 	return std::make_shared<Graph>();
 }
 
+std::shared_ptr<Graph> StorageAccessProxy::getGraphForTrail(Id originId, Id targetId, Edge::EdgeTypeMask trailType, size_t depth) const
+{
+	if (hasSubject())
+	{
+		return m_subject->getGraphForTrail(originId, targetId, trailType, depth);
+	}
+
+	return std::make_shared<Graph>();
+}
+
 std::vector<Id> StorageAccessProxy::getActiveTokenIdsForId(Id tokenId, Id* delcarationId) const
 {
 	if (hasSubject())