GH-1783 - Invoke listeners through SimpleApplicationEventMulticaster

[seonwooj0810]

Fixes #1783

Root cause

PersistentApplicationEventMulticaster invokes ApplicationListener.onApplicationEvent(…) directly, which bypasses the ClassCastException tolerance SimpleApplicationEventMulticaster.doInvokeListener(…) applies for lambda-defined listeners whose generic event type cannot be resolved by reflection. A listener created via ApplicationListener.forPayload(…) has no resolvable declared event type, so getApplicationListeners(…) reports it as a candidate for every event; publishing a non-payload event such as ContextRefreshedEvent then fails the lambda's implicit cast to PayloadApplicationEvent. Because the multicaster registers itself as the applicationEventMulticaster bean, merely adding event externalization to an application turns a listener that worked before into a context refresh failure.

Change

PersistentApplicationEventMulticaster now extends SimpleApplicationEventMulticaster and delegates the listener invocation to invokeListener(…). Both multicastEvent(…) overloads stay overridden, so the publication-registry logic is unchanged; the fix restores the invocation semantics of the multicaster that is being replaced and, as a side effect, honors a configured ErrorHandler.

Tests

Added PersistentApplicationEventMulticasterUnitTests.doesNotPropagateClassCastExceptionOfNonMatchingLambdaListener(), which registers an ApplicationListener.forPayload(…) listener and multicasts a plain ApplicationEvent. It fails on main with exactly the reported exception and passes with the fix.

Verification done: reproduced the reported ClassCastException with a failing test on upstream/main (same stack frame as the issue, PersistentApplicationEventMulticaster.multicastEvent); ./mvnw test -pl :spring-modulith-events-core — 49 tests, all green; ./mvnw test -pl :spring-modulith-events-tests -am — events-core, events-jpa (59) and the integration example all green. Checked that PersistentApplicationEventMulticaster is not referenced as an AbstractApplicationEventMulticaster anywhere else in the codebase.