Fix#8620 Inconsistency when saving workflow 'name' tag of the file saved as "new workflow"

[leehaut]

Fix #8620

Summary

Creating a pipeline or workflow stores the default name (New pipeline / New workflow). With "Synchronize name with filename" enabled (the default), the UI shows the name derived from the filename, but XML serialization writes the stored name field. Saving as Test Pipeline.hpl therefore left <name>New pipeline</name> in the file. The same happened for workflows.

getXml() now copies that filename-derived name into the persisted field before serialization, for both pipelines and workflows. A custom name is left unchanged when synchronization is turned off. Renaming a closed file in the explorer uses the same getXml() path, so that case is covered too.

Test plan

• New pipeline, do not open the properties dialog, save as Test Pipeline.hpl. The file contains <name>Test Pipeline</name>, not New pipeline
• Same steps for a workflow saved as Test Workflow.hwf: <name>Test Workflow</name>.
• Turn off "Synchronize name with filename", set a custom name, save, and confirm <name> keeps that custom name.
• ./mvnw -pl engine test -Dtest=PipelineMetaTest,WorkflowMetaTest