fix: prevent memory leaks from AbortController closures (#12024)

packages/opencode/src/util/abort.ts

@@ -0,0 +1,35 @@
+/**
+ * Creates an AbortController that automatically aborts after a timeout.
+ *
+ * Uses bind() instead of arrow functions to avoid capturing the surrounding
+ * scope in closures. Arrow functions like `() => controller.abort()` capture
+ * request bodies and other large objects, preventing GC for the timer lifetime.
+ *
+ * @param ms Timeout in milliseconds
+ * @returns Object with controller, signal, and clearTimeout function
+ */
+export function abortAfter(ms: number) {
+  const controller = new AbortController()
+  const id = setTimeout(controller.abort.bind(controller), ms)
+  return {
+    controller,
+    signal: controller.signal,
+    clearTimeout: () => globalThis.clearTimeout(id),
+  }
+}
+
+/**
+ * Combines multiple AbortSignals with a timeout.
+ *
+ * @param ms Timeout in milliseconds
+ * @param signals Additional signals to combine
+ * @returns Combined signal that aborts on timeout or when any input signal aborts
+ */
+export function abortAfterAny(ms: number, ...signals: AbortSignal[]) {
+  const timeout = abortAfter(ms)
+  const signal = AbortSignal.any([timeout.signal, ...signals])
+  return {
+    signal,
+    clearTimeout: timeout.clearTimeout,
+  }
+}