Drilling into subprojects on the Projects list

A project can have subprojects. On the Projects list, parent projects now show as an expandable tree: click a parent to expand it and see its subprojects nested underneath, then drill in from there — all without leaving the list.

Prefer the old flat view? Use the Flatten toggle to collapse the tree into a single plain list of every project. Toggle it back to return to the tree. Search and filters still work either way — a search reaches subprojects even when they're nested, and the row actions (open, edit, etc.) are the same on every row.