🌋 Lava Dome Growth: Bingham Yield-Stress Extrusion, Collapse and Block-and-Ash Runout - 2D Profile, Volume and Runout Desk

2D companion: Viscous lava extrudes from a crater vent and piles into a dome whose height is set by the yield stress. A lubrication model grows the dome, a collapse trigger releases a block-and-ash flow, and the Heim ratio sets how far it runs.