[ZEPPELIN-6595] Derive a reloaded note's leaf name from the note tree - #5498

What is this PR for?

NoteManager.NoteNode.loadAndProcessNote rebuilt a reloaded note's path from the tree for the folder but from the JSON name field for the leaf. A renamed note whose JSON had not been rewritten came back under its old name, which is the only reason moveNote re-saved after a rename (and the source of the ZEPPELIN-5858 race).

This PR takes the leaf from the tree as well (note.setPath(getNotePath())) and removes the rename re-save block in moveNote, together with its disk write and lock nesting.

Trade-off: after a rename, the name field in the on-disk JSON stays behind until the note is next saved. Zeppelin does not read it for location, and exportNote serializes the in-memory note, so exports are unaffected.

What type of PR is it?

Improvement

Todos

• - Derive the leaf name from the note tree on reload
• - Remove the rename re-save in moveNote
• - Add/update tests

What is the Jira issue?

ZEPPELIN-6595

How should this be tested?

• NoteManagerTest#testReloadAfterRenameDerivesLeafNameFromTree: uses a JSON round-trip repo (like S3/GCS/FileSystem) so a stale name actually surfaces on reload.
• NoteManagerMoveResaveRaceTest#testRenameDoesNotReloadOrResave: repurposed from the ZEPPELIN-5858 test; asserts moveNote no longer reloads from the repo and still leaves exactly one .zpln file.
• NotebookTest#testMoveNote: now asserts the file location and the reloaded path/name instead of the JSON name content.

Questions:

• Does the license files need to update? No
• Is there breaking changes for older versions? No
• Does this needs documentation? No