refactor(audit): rename findDedupedActivityFeed to findRolledUpActivityFeed

The method no longer deduplicates by hour-trunc — it performs session-style
rollup via LAG()+120-min gap. Rename aligns the public name with the
behavior.

Part of #285.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

backend/src/main/java/org/raddatz/familienarchiv/audit/AuditLogQueryRepository.java

@@ -96,7 +96,7 @@ public interface AuditLogQueryRepository extends JpaRepository<AuditLog, UUID> {
             ORDER BY ag.happened_at DESC
             LIMIT :limit
             """, nativeQuery = true)
-    List<ActivityFeedRow> findDedupedActivityFeed(
+    List<ActivityFeedRow> findRolledUpActivityFeed(
             @Param("currentUserId") String currentUserId,
             @Param("limit") int limit);
 

backend/src/main/java/org/raddatz/familienarchiv/audit/AuditLogQueryService.java

@@ -17,7 +17,7 @@ public class AuditLogQueryService {
     }
 
     public List<ActivityFeedRow> findActivityFeed(UUID currentUserId, int limit) {
-        return queryRepository.findDedupedActivityFeed(currentUserId.toString(), limit);
+        return queryRepository.findRolledUpActivityFeed(currentUserId.toString(), limit);
     }
 
     public PulseStatsRow getPulseStats(OffsetDateTime weekStart, UUID userId) {