feat(rest-client): allow customizing retry config via constructor option [backport stable/8.8]

[jwulf]

Backport of commit cea5ab8 to stable/8.8.

Closes #808

Changes

Adds an optional retry parameter to the CamundaRestClient constructor options, allowing users to customize the HTTP retry configuration. Falls back to GotRetryConfig defaults when not provided.

const client = new CamundaRestClient({
  config: { ... },
  retry: {
    limit: 5,
    statusCodes: [429, 503],
    methods: ['GET', 'POST'],
  }
})

[github-actions]

Released in v8.8.12 (npm: @camunda8/sdk@8.8.12).