feat: add generation cancel job functionality and improve job handling

- Introduced `generationCancelJob` command ID in `commands/ids.ts`.
- Added `GenerationCancelJobPayload` type in `commands/payloads.ts`.
- Enhanced job status to include "cancelled" in `editor/state.ts`.
- Updated `runGenerationJob` to accept an `AbortSignal` and handle cancellation.
- Implemented cancellation logic in `runGenerate` and related functions.
- Added tests for job cancellation in `operations/generation/workflow.test.ts`.
- Improved layer rendering logic to prevent stack overflow in `editor/document-indexes.ts`.
- Added raster size assertions in `platform/browser/rasterLimits.ts` for image processing limits.
- Enhanced image file handling to check for size limits in `platform/browser/imageFiles.ts`.
- Updated UI components to reflect job cancellation state in `view/GenerationJobStatus.tsx` and `view/bottom-controls/GenerateActionControls.tsx`.

editor/document-indexes.test.ts

@@ -67,6 +67,17 @@ describe("document read indexes", () => {
     expect(visited).toEqual(["group", "target", "mask"]);
     expect(layers.map((layer) => layer.id)).toEqual(["mask", "target", "group"]);
   });
+
+  test("indexes pathological nesting without recursive stack overflow", () => {
+    let layers: Layer[] = [raster("leaf", "Leaf", "asset-nested", { x: 80, y: 10 }, { x: 2, y: 3 })];
+    for (let depth = 0; depth < 10_000; depth += 1) layers = [group(`group-${depth}`, `Group ${depth}`, layers)];
+    const deepDocument = { ...document, artboards: [{ ...document.artboards[0]!, layers }] };
+
+    const index = createDocumentReadIndex(deepDocument);
+
+    expect(index.layerById.size).toBe(10_001);
+    expect(resolveIndexedLayerBounds(index, layers[0]!)).toEqual({ x: 80, y: 10, w: 40, h: 30 });
+  });
 });
 
 function raster(