furniture-fit-checkerlisted

# Furniture Fit Checker 🛋️📏 The classic disaster: sofa bought online, delivery guys arrive, it doesn't make the corner at the top of the stairs — now you own a return-shipping nightmare. Or: desk fits the wall but blocks the door swing. This skill runs the geometry **before money changes hands**. ## Overview Three checks, one tool (`scripts/fit_checker.py`): 1. **Path check** — can the item pass a doorway/corridor/stairs? The moving-industry insight: a rigid box passes through an opening if it can be **tilted diagonally**. For a rectangular item (W×H×D) and a doorway (w×h), the effective clearance is the diagonal √(W²+D²) compared against the door width — plus corner-turning between corridor walls with the inner-diagonal trick. Handles: - doorway width vs item diagonal (item height vs door height) - L-shaped corner between corridors (inner-corner + outer-wall check) - straight staircase width vs diagonal, landing 180° turns - elevator cab diagonal (door + interior) 2. **Room fit** — does it fit where you want it, with **walkways ≥ 30 in / 75 cm** (interior-design standards: 75-90cm paths, 90+ around dining)? Checks wall-length fit, walkway to opposing furniture/door, door-swing clearance, and radiator/vent obstruction warnings. 3. **Floorplan preview** — ASCII render of the room with the furniture placed, so you can *see* the walkways before committing. Everything in metric or imperial (auto-detected per value with explicit unit s