Thread stages v0.6.4

Patch Changes

• d051765: Let an uncolored sidebar icon take the color of the label beside it. Both
  plugins pinned a token instead — text-subtle-foreground on bb's group
  headers, text-muted-foreground/70 on a stage row — and neither token moves
  when a theme moves its ink. The icon came out brighter than its label in the
  default theme and darker in the ChatGPT one, from the same two lines. Inheriting
  matches bb's own pairing of an icon with its label, in any theme.