Keep OkHttp SSE callbacks attached to the correct Allure test

[baev]

Context

Adds an Allure-aware server-sent events factory for OkHttp so listener steps and HTTP exchange attachments are assigned to the test or fixture that opens each stream. Shared clients, factories, requests, and listeners can be created before the test; context is captured when the event source is opened, preventing reused dispatcher threads from carrying the first test’s context into later tests.

Use the new factory alongside the Allure interceptor:

OkHttpClient client = new OkHttpClient.Builder()
        .addInterceptor(new AllureOkHttp3())
        .build();

EventSource.Factory eventSourceFactory = AllureEventSources.createFactory(client);
EventSource eventSource = eventSourceFactory.newEventSource(request, listener);

Event sources opened outside a running Allure test or fixture do not report callbacks against stale test results.

fixes #1036

Checklist

• Sign Allure CLA
• Provide unit tests

[github-actions]

Allure Report Summary

	Name	Duration	Stats	New	Flaky	Retry	Report
	Allure Java – Pull request #1401	29m 39s	2228	4	0	0	View
	Allure Java GitHub actions run (2026-08-28T09:21:15.067Z)	29m 39s	2228	4	0	0	View