feat: enhance layer mask handling and opacity management

- Introduced `getLayerMask` utility to streamline layer mask retrieval.
- Updated layer rendering logic to incorporate layer masks and opacity adjustments.
- Added functionality to prevent dropping a group into its descendants.
- Enhanced image texture rendering to support opacity parameters across various rendering functions.
- Implemented group layer bounds application for better scaling and positioning.
- Added tests to ensure correct behavior when handling layer masks and group layers.
- Created new types for asset generation provenance to track generated assets more effectively.

input/selection.ts

@@ -2,6 +2,7 @@ import { commandIds } from "@commands/ids";
 import type { Dispatch } from "@commands/dispatcher";
 import type { ImageDocument } from "@core/document";
 import type { Layer } from "@core/layer";
+import { getLayerMask } from "@core/layer-mask-utils";
 import { resolveTransformTargetBounds, viewportPointToDocumentPoint, type InputViewportState } from "./document-geometry";
 import type { PointerInputEvent } from "./pointer";
 
@@ -65,9 +66,9 @@ function findTopmostLayerInTreeAtPoint(document: ImageDocument, layers: Layer[],
 
 function collectMaskLayerIds(layers: readonly Layer[], ids = new Set<string>()): Set<string> {
   for (const layer of layers) {
-    if (layer.clippingMask) ids.add(layer.clippingMask.maskLayerId);
+    const layerMask = getLayerMask(layer);
+    if (layerMask) ids.add(layerMask.maskLayerId);
     if (layer.type === "group") collectMaskLayerIds(layer.children, ids);
   }
   return ids;
 }
-