A directory whose cascade default_tool is "tables" (mdl/rsk/ssr and any
operator-configured table dir) now shows in the browse tree as a leaf with
a table icon — no expand chevron — and clicking it opens the tables tool in
the preview pane (an iframe scoped to the dir, mirroring grid.js's
classifier embed) instead of expanding/navigating into the folder.
Detection rides the cascade, not hardcoded names: the directory listing now
carries a per-entry default_tool hint (listing.FileInfo.DefaultTool, set via
zddc.DefaultToolAt for both on-disk children and the virtual canonical peers
mdl/rsk/ssr). Browse's util.isTableLeaf(node) keys off it; tree.js renders
the leaf, events.js routes its click/Enter to the preview (excluding it from
expand/navigate), and preview.js renders the iframe at the dir's NO-SLASH
URL (the default_tool route — <dir>/tables.html 404s for a virtual dir).
Server mode only (the hint is absent on file://, so offline folders stay
ordinary expandable dirs). Validated end-to-end in a containerized browser:
mdl/rsk/ssr are leaves, normal folders keep their chevrons, and clicking mdl
loads the tables view inline without navigating.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>