[codex] fix adapter mesh bounds overflow

[madawei2699]

Summary

Fixes #125.

The mesh adapter now computes global XYZ bounds in a bounded iterative pass over parsed triangle vertices. It no longer flattens the entire triangle list or passes every mesh reference to Math.min and Math.max. The parser, fan triangulation, normalization, voxelization, ordering, deduplication, and VoxelPlan behavior remain unchanged.

Cause and fix

The Sydney Opera House input reported by MinePilot #106 contains 82,144 vertices and 129,780 triangles (389,340 triangle-vertex references, about 7.5 MiB). The former global bounds calculation spread all references into Math.min/Math.max; on Node v22.22.3, argument counts at this scale throw RangeError: Maximum call stack size exceeded before voxelization. computeMeshBounds now updates three minima and maxima while visiting each triangle vertex and avoids the extra flattened array.

Regression and acceptance evidence

• Added a generated OBJ with 50,000 repeated triangular faces (150,000 vertex references). With target height 1 and a 1×1×1 output budget, conversion succeeds with the correct size and one in-bounds block. A direct 150,000-argument spread probe on Node v22.22.3 reproduces the prior RangeError.
• Ran the available normalized Sydney OBJ (5,750,809 bytes) with the requested settings: targetHeight 64, surface mode, maxBlocks 10,000,000, and minecraft:quartz_block. It passed bounds and produced a VoxelPlan sized 167×64×113 with 103,811 blocks.
• Existing exact fixture checks pass unchanged.

Validation

• pnpm --filter @i365dev/craftdag-adapter-mesh test — 7 passed.
• pnpm --filter @i365dev/craftdag-adapter-mesh typecheck — passed.
• pnpm build — passed.
• pnpm test — 219 passed.
• pnpm typecheck — passed.
• pnpm lint — passed.
• git diff --check — passed.