Paginate deleteByConversationId to delete all events

[vaquarkhan]

Summary

AgentCoreShortTermMemoryRepository.deleteByConversationId() calls listEvents once with maxResults(pageSize) but never paginates using nextToken. If a conversation has more events than pageSize, the remaining events are silently orphaned — never deleted, never visible, wasting storage indefinitely.

Root Cause

The fetchAllEvents() method in the same class correctly implements pagination with a do/while loop checking nextToken. The deleteByConversationId() method was simply missing the same pattern.

Changes

• AgentCoreShortTermMemoryRepository.java — Added do/while pagination loop with nextToken handling in deleteByConversationId(), matching the existing fetchAllEvents() pattern

Before vs After

// BEFORE — single page, orphans remaining events
var events = client.listEvents(request).events();
events.forEach(event -> client.deleteEvent(...));

// AFTER — paginates through ALL events
String nextToken = null;
do {
    var response = client.listEvents(requestBuilder.build());
    response.events().forEach(event -> client.deleteEvent(...));
    nextToken = response.nextToken();
} while (nextToken != null);


**Testing**
mvn test -pl spring-ai-agentcore-memory — 94 tests, 0 failures
mvn spring-javaformat:apply — clean

Fixes #[52](https://github.com/spring-ai-community/spring-ai-agentcore/issues/52)