Raise room-envelope height caps from 6m to 20m

[wass08]

Level height, wall custom height, ceiling custom height, and column height were all UI-capped at 6m, which rules out tall single-space builds (climbing gyms, warehouses, halls).

Changes

• Level height slider (level selector popover): max 6 → 20
• Wall "Custom height" (panel slider + clamp, parametric descriptor): max 6 → 20
• Ceiling custom height (panel, still clamped to the level-top bound; descriptor): max 6 → 20
• Column height (panel + descriptor): max 6 → 20

20m covers the tallest realistic single-storey uses — lead-climbing walls top out around 15–18m — while keeping the sliders usable in the common 2–4m band. The caps were never enforced in core schemas; only the controls change. Slab elevation, doors, and dormer fields are deliberately untouched.

Walls/ceilings in "Follows level" mode already track the level top, so raising the level height is all a plain tall room needs.

🤖 Generated with Claude Code

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Note

Low Risk
UI-only slider/descriptor max changes; schemas and core clamping behavior are unchanged, so risk is limited to allowing taller geometry via existing controls.

Overview
Raises the UI height caps for tall single-space builds (warehouses, halls, climbing gyms) from 6m → 20m.

Updates the level-height slider in the floating level selector, plus custom-height controls and parametric descriptors for walls, ceilings, and columns. Ceiling custom height remains clamped to the level-top bound. Core schemas were never enforcing the old 6m limit—only the controls change.

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