Background CPU waste caused by ActiveChartHandler

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What happened: About half of the background CPU used by Portmaster is caused by frequent SQLite queries by ActiveChartHandler. Even when the UI is minimized to the tray.

What did you expect to happen?: When the UI is minimized to tray, components that perform background queries should be removed from the tree.

How did you reproduce it?: Close the Portmaster UI window.

Debug Information: N/A