0.12.0 — the floor is a game

The floor is a game now (ADR-0063)

• The 2.5D office is rebuilt from scratch on canvas: isometric room, checker carpet, walls + window, doors with #signs, glass meeting table, desks with monitors that light up while their person works.
• Procedural pixel people from each person's look (skin/hair/top): 4-frame walk, sit, type poses, shadows, name tags, lead star.
• Live accounts type out as speech bubbles above heads; a status dot colors the pose (thinking / working / writing).
• Click carpet to walk (BFS path around obstacles), click a person to DM, click a door to enter, drag to pan, wheel to zoom.
• floor.json / looks.json contracts unchanged. Layout + pathing moved to a pure bun-tested module (floor-iso.js).