Remove the redundant header row, tighten spacing, and square off question cards. Also adjust answered question container styling to match tool call layout.
Use tokenized border contrast so dark mode borders stay subtle, keep instance tab status dots vivid in dark themes, and adjust tool-call code block header background via a dedicated token.
Add a 3-state theme toggle in folder selection and instance tabs, and update tokens/styles so light mode has readable contrast. Sync MUI surfaces and Shiki highlighting to CSS variables to prevent stale colors when switching themes.