Add Chromium-only Blender WebEngine parity work

web/protocol/modifier.ts

@@ -0,0 +1,27 @@
+import type { ModifierIR } from "./scene-ir";
+
+function fnv1a(value: string): number {
+  let hash = 0x811c9dc5;
+  for (let index = 0; index < value.length; index++) {
+    hash ^= value.charCodeAt(index);
+    hash = Math.imul(hash, 0x01000193);
+  }
+  return hash >>> 0;
+}
+
+/** Hashes evaluated modifier identity/state, excluding display timestamps. */
+export function modifierStackHash(stack: readonly ModifierIR[] | undefined): string {
+  const canonical = (stack ?? []).map((modifier) => ({
+    uuid: modifier.uuid,
+    type: modifier.type,
+    enabled: modifier.enabled,
+    showViewport: modifier.showViewport,
+    showRender: modifier.showRender,
+    showEditMode: modifier.showEditMode,
+    showOnCage: modifier.showOnCage,
+    parameters: modifier.parameters,
+    dependsOn: modifier.dependsOn,
+    evaluationStatus: modifier.evaluationStatus,
+  }));
+  return `mod-${fnv1a(JSON.stringify(canonical)).toString(16).padStart(8, "0")}`;
+}