- renameFolder/moveFolder UPDATE and deleteFolderSoftRescue DELETE now
carry an explicit port_id predicate so the write is bounded to the
same tenancy the pre-fetch verified, defending against future
refactors that drop or reorder the ownership check.
- FolderRow's collapsed-children chevron is `invisible` for layout
purposes, but it was still in the tab order with a misleading
Expand/Collapse aria-label. Add aria-hidden + tabIndex=-1 when no
children so keyboard users skip it.
Surfaced by post-implementation review (subagent code-review pass).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>