refactor(src): split oversized modules

src/agents/pi-embedded-runner/abort.ts

@@ -0,0 +1,10 @@
+export function isAbortError(err: unknown): boolean {
+  if (!err || typeof err !== "object") return false;
+  const name = "name" in err ? String(err.name) : "";
+  if (name === "AbortError") return true;
+  const message =
+    "message" in err && typeof err.message === "string"
+      ? err.message.toLowerCase()
+      : "";
+  return message.includes("aborted");
+}