Make the auto-reconnect backoff configurable in the TypeScript SDK

The connection manager retries dropped connections with an exponential backoff that is fixed at module-level constants.
They are hard coded to start at 1000ms and maxes out at 30_000ms.

There is no way for an app to tune these. Apps that want faster recovery, or a gentler backoff, currently cannot change them. I for one require different values as my player base is 95% mobile browser in flaky connections areas.

Proposal: let the delays be set on the builder, e.g.

DbConnection.builder()
  .withUri(...)
  .withDatabaseName(...)
  .withReconnectOptions({ baseDelayMs: 500, maxDelayMs: 10_000 })

Open question for maintainers: field naming. The linked PR uses baseDelayMs / maxDelayMs to match the existing constant names, with baseDelayMs documented as the minimum (first-retry) delay. minDelayMs / maxDelayMs may read better for consumers. Happy to rename.