Build Anticipation with NPC “?” Placeholder Update

What’s New

• Per‑NPC Reveal Switch
  Each NPC entry gains a revealSwitchId field. While that switch is OFF, their portrait area displays a “?” placeholder instead of going blank. Flick the switch on, and their name, description, and heart meter appear as normal.

• Placeholder Character
  We now draw a large, centered “?” in the portrait box (using ColorManager.textColor(0)) when the panel is locked.