v0.7.0

Added

• Settings window (⌘,) with an Appearance picker: follow the system, or
  force Light or Dark. The choice applies immediately and persists.
• The About panel now links to teebe.io, the GitHub repo and the author's X
  account.

Fixed

• A pinned window never showed up in App Exposé or Mission Control. It now
  floats only while another app is in front, so it is listed whenever teebe is
  active; behaviour while working in other apps is unchanged.
• With the window pinned, closing the About panel with ⌘W could get the app
  quit a second later by window-tracking utilities that overlook floating
  windows. Same fix as above, plus a guard in the app's own last-window check.