fix: restore wall plane-bound defaults (draft, panel, self-heal)

[wass08]

What does this PR do?

Fixes the fallout of the terrain-sculpt regression (#564-era) that detached walls from the plane-bound vertical model, across three layers:

• Drafting — createWallOnCurrentLevel no longer stamps the draft ghost's height/supportOffset/ground host onto walls drawn on flat ground or on slabs. Stamping is gated on drafted ground intent with sculpted terrain actually present (the terrain exception), so every other wall commits plane-bound: no stored height, top at the storey plane, base re-elected from slab support. Non-ground chains re-resolve the pointed surface per commit for supportCap.
• Wall panel — the inspector is reworked around the vertical model: Top is "Follows level" (plane-bound, shows the resolved height) vs "Custom height" (slider, seeded from the effective height so geometry doesn't jump on detach); Bottom is "Auto" vs "Fill to terrain", and the infill toggle no longer materializes an explicit height. Both "Follows level" and "Auto" perform a one-click repair of regression-era walls: they drop the stamped draft offset and a ground host that no sculpted terrain supports. "Auto" fires even when already selected, so walls that display Auto while secretly ground-pinned heal in place, keeping their custom height.
• Self-heal on load — the shared vertical canonicalization strips a terrain-less ground host (plus draft offset) when the un-pinned election would land the wall on a slab its base is currently embedded in — the buried state that z-fights the slab's side faces. Deliberately narrow: a wall intentionally grounded under a hovering deck is not buried and keeps its pin, and scenes with sculpted terrain are skipped wholesale (the pin is load-bearing there, and the live terrain field isn't visible to this pure, authority-shared pass).

Includes 2 drafting regression tests and 5 canonicalization tests. Suites: core 1004, nodes 944, editor 600 — green; turbo check-types 10/10.

How to test

1. bun dev, open a project, draw a slab, then draw a wall on it with the 3D wall tool. Select the wall: Top should read "Follows level" and the persisted node should have no height/supportOffset/supportSlabId.
2. Draw a closed room on flat ground (auto slab forms). The wall bases should land on the slab top — no striped z-fighting band at the base.
3. Load a scene containing a regression-era wall (supportSlabId: "ground" + stamped height, buried in a room slab). On load the pin is stripped and the base lands on the slab, keeping the custom height.
4. In the wall panel, toggle Top → "Custom height" (slider appears seeded with current height) → back to "Follows level" (height clears, base re-elects). Toggle Bottom → "Fill to terrain" and back to "Auto" on a flat scene: geometry is identical (infill is terrain-only).
5. On a sculpted-terrain scene, confirm terrain-drafted walls still freeze their construction plane and "Fill to terrain" still fills down to the sculpted ground.

Screenshots / screen recording

N/A — validated via before/after base close-ups during development (z-fight band at the wall base gone once the ground pin is stripped); happy to attach a clip on request.

Checklist

• I've tested this locally with bun dev
• My code follows the existing code style (run bun check to verify)
• I've updated relevant documentation (if applicable)
• This PR targets the main branch

---

Note

Medium Risk
Changes serialized wall vertical fields, load-time migration shared by editor and authority, and commit-time drafting behavior—high user visibility but narrow rules and solid test coverage.

Overview
Restores the plane-bound wall vertical model after terrain-sculpt-era regressions that stamped draft ghost data (height, supportOffset, supportSlabId: 'ground') onto walls that should stay storey-bound.

Drafting — createWallOnCurrentLevel only freezes construction plane/height when the chain is a ground draft on sculpted terrain; flat ground and slab starts commit without stored height, offset, or ground host. The 3D wall tool re-resolves the pointed support surface on each segment commit except ground-hosted chains.

Load migration — migrateVerticalSceneNodes strips terrain-less ground pins (and draft offsets) when slab election would bury the wall base in a floor slab; skips sculpted-terrain sites and preserves pins under hovering decks.

Wall panel — Top is “Follows level” vs “Custom height”; Bottom is “Auto” vs “Fill to terrain”. Toggling back to storey/auto applies wallBaseRepairPatch to clear bogus offsets and ground hosts without terrain support.

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Repair clears terrain wall offsets

Medium Severity

wallBaseRepairPatch always clears supportOffset, even when it keeps a terrain-backed supportSlabId of ground. Clicking already-selected Bottom Auto (or Top Follows level) therefore drops the frozen construction offset on legitimate terrain-drafted walls, so the base jumps while the ground host remains.

Additional Locations (1)

• packages/nodes/src/wall/panel.tsx#L202-L211

 

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