Layer Modeler QGIS 4 compatibility

QGIS plugin for hydrostratigraphic modelling. Adds a menu item to the "Plugin" menu that enforces stratigraphic order across many interpolated raster surfaces at once. Layer boundaries interpolated independently, for example by IDW from interpretation PointZ layers, routinely cross each other where the interpretation is sparse. The plugin clips crossing surfaces to their vertical midpoint in a single pass over the whole stack, replacing the manual pairwise raster calculator workflow. Layers can be marked immutable, such as a terrain surface or a fixed bedrock horizon, in which case crossing surfaces collapse onto the immutable layer instead of meeting it halfway. Adjusted surfaces are written beside their source raster with an "_adjusted" suffix.