fix(core-internal): preserve error cause and support ErrorOptions in SdkError - #2665

Summary

Fixes #2657

When network or protocol errors occur, telemetry collectors and error tracers (e.g. Sentry, Pino, OpenTelemetry) rely on the standard ECMAScript 2022 Error.cause property on Error instances.

Previously, SdkError accepted data?: ErrorData but did not pass options?: ErrorOptions to super(message, options). As a result, when classifyNetworkError or custom error handlers constructed an SdkError, the underlying root cause (e.g. ENOTFOUND, ECONNREFUSED, or TypeError) was not accessible via standard error.cause.

Changes

1. Updated SdkError constructor to support options?: ErrorOptions while maintaining full backward compatibility with data?: ErrorData.
2. Automatically extracted cause from data.cause or direct options.cause and passed to super(message, errorOptions).
3. Added unit tests in packages/core-internal/test/types/errorSurfacePins.test.ts verifying that error.cause is preserved across construction styles.

Verification

pnpm --filter @modelcontextprotocol/core-internal test test/types/errorSurfacePins.test.ts
# 13 passed