Summary

Adds comprehensive tests for the event handler dispatch mechanism, covering duplicate handler registration, unsubscription behavior, and threading guarantees.

JUnit Tests (SessionEventHandlingTest)

7 new tests added:

• testDuplicateTypedHandlersBothReceiveEvent — two handlers for the same event type both fire
• testDuplicateGenericHandlersBothFire — two generic handlers both fire
• testUnsubscribeOneKeepsOther — unsubscribing one same-type handler leaves the other active
• testAllHandlersInvoked — 3 handlers all called (containsAll since ConcurrentHashMap order is not guaranteed)
• testHandlersRunOnDispatchThread — handler executes on the thread that calls dispatchEvent()
• testHandlersRunOffMainThread — handler does NOT run on the test/main thread when dispatched from background
• testConcurrentDispatchFromMultipleThreads — 100 events from 10 concurrent threads, all delivered without loss

All 16 JUnit tests pass (9 existing + 7 new).