The v5 restyle turned the tab rows, the search field and the workspace
switcher into full pills, which read too round at this density. Put
back CARD_RADIUS on the rows, rounded_lg on the search field and
rounded_md on the switcher (and its rename field), keeping the 28px
row height. PILL_RADIUS has no users left and goes with them.
- Rails share the window fill and are separated by a hairline only;
the current tab is a neutral selected step plus a semibold title
instead of the blue navigation wash (the unused role is removed).
- Default Light theme takes ink #0F1419 and accent #1F6BF0; the caret
follows the accent.
- Sidebar: 28px pill rows with 18px avatars (two-line rows keep card
corners), pill search field and workspace switcher, group headings
in body ink with the chevron shown only when folded.
- Right panel: word tabs (Info / Changes / Files) with an underline
bar on a closing hairline. The Changes count is dropped before any
label is cut, and the panel floor grows with the measured labels so
the chrome tiles are never pushed off the edge.
- Headings are no longer uppercased; popovers use a 10px radius.
- docs/design-system.md updated to match.
l0ng-ai