devel/massif-visualizer: Update to 24.12.2 for KDE Gear and pass maintership

massif-visualizer is shipped with KDE Gear distribution,
so pass the maintership to kde@ which would like to
maintain it.

• Pass the port to kde@ and connect to KDE Gear distribution.
• Depend on graphics/kgraphviewer.
• Clean up KDE/Qt dependencies.

PR: 284968
Reported by: mack