PRD: D3-TUI / D2-Visor

Product Goal

Build a resilient, immersive “vibe coding” cockpit where a retro handheld frontend controls and observes modern Hermes AI work on a Raspberry Pi backend. The frontend must ultimately be a Dreamcast game executable that runs through the RG40XXV/KNULLI Dreamcast path, styled after the D2 title screen and adapted into a usable command interface.