ANW-1831: Fix 404 console error for PUI resource show views

[brianzelip]

This PR fixes an issue where, when viewing a resource's show page in the public interface (e.g., /repositories/4/resources/40), the browser console showed a 404 error:

XHR GET /repositories/4/resources/40/tree/node?node=/repositories/4/resources/40 [HTTP/2 404]

ANW-1831

Problem

The _children_tree partial sets both root_node_uri and current_node_uri to the resource URI. When the tree loads:

1. setCurrentNode() is called with the resource's tree ID
2. It finds the root row and marks it as current
3. It fires node_selected_callback(root_row, tree)
4. The callback calls tree.expandNode(root_row)
5. expandNode() calls fetchNode() with the resource URI
6. The controller builds an invalid backend URL, returning 404

Fix

Add an early return in expandNode() when the row has the root-row class:

Why no new tests are included

The backend behavior is already covered by an existing controller spec, so the console error was expected before this small fix.

[coveralls]

Pull Request Test Coverage Report for Build 19916213389

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 27 unchanged lines in 9 files lost coverage.
• Overall coverage increased (+1.4%) to 80.708%

---

Files with Coverage Reduction	New Missed Lines	%
frontend/app/helpers/digital_object_helper.rb	1	87.5%
backend/app/model/accession.rb	1	98.44%
frontend/app/models/edit_mediator.rb	1	91.53%
frontend/app/controllers/application_controller.rb	1	98.3%
backend/app/controllers/job.rb	1	70.59%
indexer/app/lib/realtime_indexer.rb	4	73.53%
frontend/app/controllers/archival_objects_controller.rb	5	87.36%
frontend/app/controllers/agents_controller.rb	6	71.09%
indexer/app/lib/indexer_common.rb	7	98.96%

Totals
Change from base Build 15878865621:	1.4%
Covered Lines:	29005
Relevant Lines:	35938

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💛 - Coveralls