Fix abort signal propagation in memory store update poller

[Copilot]

The buildRunningOperation function wasn't receiving the user-provided options.abortSignal, preventing proper cancellation of ongoing poll requests.

Changes:

• Pass options parameter to buildRunningOperation to capture user-provided abort signal
• Update sendPollRequest to listen to both options.abortSignal and pollOptions?.abortSignal
• Add event listeners for both signals with proper cleanup in finally block

This aligns with the reference implementation in pollingHelpers.ts lines 53-94.

// Before: only pollOptions abort signal was handled
sendPollRequest: async (path: string, pollOptions?: { abortSignal?: AbortSignalLike }) => {
  if (pollOptions?.abortSignal?.aborted) {
    pollAbortController.abort();
  }
  // ...
}

// After: both user-provided and poll-specific signals are handled
sendPollRequest: async (path: string, pollOptions?: { abortSignal?: AbortSignalLike }) => {
  if (options?.abortSignal?.aborted) {
    pollAbortController.abort();
  } else if (pollOptions?.abortSignal?.aborted) {
    pollAbortController.abort();
  } else if (!abortSignal.aborted) {
    options?.abortSignal?.addEventListener("abort", abortListener, { once: true });
    pollOptions?.abortSignal?.addEventListener("abort", abortListener, { once: true });
  }
  // ...
}

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