bpm: the Inbox listing still reads identity links and the process instance once per task - #7175 removed one of three per-task queries and called it one statement

[delchev]

Summary

#7175 (#7141) moved the Inbox's subject variables onto the task query (findTasksWithProcessVariables + includeProcessVariables()), removing the one variable read per task. The new javadoc in BpmInboxEndpoint.mapToDTOs (lines 64-67) and in TaskServiceImpl.findTasks(type, boolean) (line 247) now claims the listing is "one statement". It is not: mapToDTO still runs two more queries per task.

components/engine/engine-bpm-flowable/src/main/java/org/eclipse/dirigible/components/engine/bpm/flowable/endpoint/BpmInboxEndpoint.java:

List<IdentityLink> identityLinks = bpmService.getTaskIdentityLinks(task.getId());                       // line 90
...
ProcessInstanceData processInstance = bpmService.getProcessInstanceById(task.getProcessInstanceId());   // line 107

getTaskIdentityLinks runs validateTask(taskId) + getIdentityLinksForTask (TaskServiceImpl.java:276-280, two statements); getProcessInstanceById runs a ProcessInstanceQuery (BpmService.java:320-323 -> BpmProviderFlowable.getProcessInstance). With the store polling ?type=assignee&limit=100 and ?type=groups every 30 s and on every route change, a 100-task inbox is still roughly 300 statements per poll - #7175 removed about a quarter of the #7141 problem and documented it as solved.

Fix

• getProcessInstanceById is keyed by processInstanceId, which many tasks share: dedupe per listing with the same computeIfAbsent pattern labelKeys already uses (line 115), or ride it on the task query (includeProcessVariables already brings the instance's variables; the business key / definition id are on the task).
• Identity links: Flowable's TaskQuery cannot include them, but IdentityLinkService/taskInvolvedUser filters or one HistoricIdentityLinkQuery over the listing's task ids replace 100 validate+query pairs with one statement.
• Fix the two javadoc claims either way.

Found reviewing #7175.