Drop `scrollbar-gutter: stable both-edges` / `stable` from `.scrollbar-thin`
and `.scrollbar-thin-edge` so scrollbars overlay content without reserving
space, fixing layout inconsistencies between overlay and classic scrollbar
environments. Restore padding that was previously reduced to compensate for the
gutter: `px-1` to `px-3` in git-log-tab, `px-2` to `px-4` in
virtualized-message-thread, and add `px-2` to sidebar-conversation-list and
session-files-tab.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Add .scrollbar-thin and .scrollbar-thin-edge utility classes in
globals.css and apply them to sidebar, file tree, git changes,
git log, session files, diff preview, and message thread panels.
Replace scattered inline webkit-scrollbar overrides with the
shared classes for consistent appearance and gutter behavior.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
