Exclude derived scene thumbnails from orphan findings

module.json

@@ -2,7 +2,7 @@
   "id": "kosmos-storage-audit",
   "title": "Kosmos Storage Audit",
   "description": "Analyzes media references and risky storage locations across Foundry data and public roots.",
-  "version": "0.0.19",
+  "version": "0.0.20",
   "compatibility": {
     "minimum": "13",
     "verified": "13"

scripts/core/finding-engine.js

@@ -211,6 +211,7 @@ function wildcardToRegExp(pattern) {
 }
 
 function shouldReportOrphan(file, references) {
+  if (isDerivedSceneThumbnail(file)) return false;
   if (file.riskClass === "stable-world") {
     const worldId = file.ownerHint.ownerId;
     return references.some(reference => reference.sourceScope?.ownerType === "world" && reference.sourceScope.ownerId === worldId);
@@ -224,6 +225,11 @@ function shouldReportOrphan(file, references) {
   return false;
 }
 
+function isDerivedSceneThumbnail(file) {
+  const path = String(file.path ?? "");
+  return /^worlds\/[^/]+\/assets\/scenes\/[^/]+-thumb\.(?:png|webp)$/u.test(path);
+}
+
 export function createFileRecord(locator, size = null) {
   return {
     ...locator,

tests/scene-thumbnail-orphan-test.mjs

@@ -0,0 +1,30 @@
+import assert from "node:assert/strict";
+import { buildFindings, createFileRecord } from "../scripts/core/finding-engine.js";
+import { createFileLocator } from "../scripts/core/path-utils.js";
+
+const files = [
+  createFileRecord(createFileLocator("data", "worlds/demo-world/assets/scenes/exampleScene-thumb.webp"), 1234)
+];
+
+const references = [
+  {
+    sourceType: "world-document",
+    sourceScope: { ownerType: "world", ownerId: "demo-world", systemId: "demo-system", subtype: "actors" },
+    sourceLabel: "Actor demo",
+    rawValue: "worlds/demo-world/assets/actors/portrait.webp",
+    normalized: {
+      ...createFileLocator("data", "worlds/demo-world/assets/actors/portrait.webp"),
+      targetKind: "local-file"
+    }
+  }
+];
+
+const findings = buildFindings({ files, references });
+
+assert.equal(
+  findings.some(finding => finding.kind === "orphan-file" && finding.target.locator === "data:worlds/demo-world/assets/scenes/exampleScene-thumb.webp"),
+  false,
+  "derived scene thumbnails should not be reported as orphaned"
+);
+
+console.log("scene-thumbnail-orphan-test: ok");