HUD pen fix and one-card HUD
Lead: The pen opened the whole HUD full screen instead of the drawing layer, so you had no way out. That is fixed. The HUD is now one card with no frosted window around it, the same look as Claude's quick chat. Two PRs are open and not merged yet.
What broke
The pen opens a full-screen window at /hud/annotate. ShellApp rendered the HUD for every /hud path, so that window showed a grey HUD over the whole screen with no Done button. Escape closed the HUD and left the overlay open.
ShellApp renders only the drawing view at /hud/annotate, on a transparent page. Done or Escape closes the layer.
Pen layer after the fix

HUD after: light

HUD after: dark

Reference

Status
| Item | State ||---|---|| ai #883 code | ok open, not merged || platform #1953 docs | ok open, check_links 0 problems || Typecheck | ok clean || Agent mode row inside the card | warn not seen signed out; check in the app || Real Electron window | warn not checked; needs a Desktop build |