bad780de9d
The last item of the Stage-10 editor-UX batch. The Project panel's fixed typed-folder listing becomes a real file explorer over assets/: - breadcrumbs + double-click folder navigation, "➕ New Folder", inline rename rows, context menus (Open / Rename / Delete), drag a row onto a folder (or "..") to move it, drag files in from the OS to import into the current folder, double-click to open (scripts via the external-editor flow, others via xdg-open). - All behavior lives egui-free in editor/src/explorer.rs (listing, breadcrumbs, name validation/uniquing, create/rename/move/delete/ import) and is unit-tested; the shell only renders it. Renames and moves ride the uid-preserving AssetDatabase ops so saved AssetRefs keep resolving; unregistered files fall back to fs::rename. Folders delete only when empty — no recursive asset deletion. - Engine: AssetDatabase::scan now walks the WHOLE assets/ tree instead of just the typed folders, so assets organised into custom folders register and survive rescans (covered by updated unit tests). File operations act immediately and bypass the undo stack, like the hierarchy's structural edits. GUI piece — needs an eye-check before promotion to main. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>