fix(director): reject cancellation during the final asset stream read

CHANGELOG.md

@@ -32,6 +32,7 @@
 - Tool string length validation counts Unicode characters correctly, including characters outside the basic multilingual plane.
 
 - Director timeline seeks cross the dateline along the short longitude arc.
+- Director assets cancelled during the final stream read are discarded with reader cleanup.
 
 - Treat explicitly current, complete empty vessel coverage as a successful update,
   clearing obsolete contacts while retaining stale or incomplete snapshots.

docs/CURRENT-STATE.md

@@ -5326,3 +5326,8 @@ datacenters, dams and the Nepal locator retain that shared credit while displaye
 
 Military fragments stitch by source identity. Different mapped parcels merge only
 when their footprints touch or contain one another, never across a seam tolerance gap.
+
+
+### fix(director): reject cancellation during the final asset stream read
+
+Re-check caller cancellation immediately after every awaited read, including done reads, while retaining reader cancellation and lock cleanup.

src/director/packs/asset-stream-cancellation.test.mjs

@@ -0,0 +1,42 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import { createAssetDirectorySource } from './source.js';
+test('cancellation during the terminating read cannot return a scene asset', async () => {
+  for (const cancel of [true, false]) {
+    const controller = new AbortController();
+    let reads = 0,
+      cancelled = 0,
+      released = 0;
+    const source = createAssetDirectorySource({
+      baseUrl: 'https://fixture.example/assets/',
+      fetchImpl: async () => ({
+        ok: true,
+        headers: new Headers({ 'content-type': 'application/octet-stream' }),
+        body: {
+          getReader() {
+            return {
+              async read() {
+                reads++;
+                if (reads === 1)
+                  return { done: false, value: new Uint8Array([1, 2]) };
+                if (cancel) controller.abort();
+                return { done: true };
+              },
+              async cancel() {
+                cancelled++;
+              },
+              releaseLock() {
+                released++;
+              },
+            };
+          },
+        },
+      }),
+    });
+    const pending = source({ path: 'scene.bin', signal: controller.signal });
+    if (cancel) await assert.rejects(pending, { name: 'AbortError' });
+    else assert.deepEqual([...(await pending).bytes], [1, 2]);
+    assert.equal(cancelled, 1);
+    assert.equal(released, 1);
+  }
+});

src/director/packs/source.js

@@ -41,6 +41,7 @@ export function createAssetDirectorySource({
       for (;;) {
         signal?.throwIfAborted();
         const { done, value } = await reader.read();
+        signal?.throwIfAborted();
         if (done) break;
         length += value.byteLength;
         if (length > maxBytes) throw new Error('Asset exceeds byte limit');