Sub-phase A of the window-manager → inventory → paperdoll arc. A named-
window registry on UiRoot (Show/Hide/Toggle/BringToFront) + raise-on-click
+ wiring the EXISTING InputAction.ToggleInventoryPanel (already F12-bound,
retail-faithful) through OnInputAction, toggling a throwaway placeholder
inventory window that Sub-phase B replaces with the real gmInventoryUI.
Cross-check correction vs the handoff: retail's inventory key is F12, not
I (I = Laugh emote per retail-default.keymap.txt:246). Reuses the existing
action, so no new keybind — rebindable via the Settings panel.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
