[SpectralDragon]

Adds a playable Mesh Terrain Workshop in Ada Studio. Join a static model to the ground, move it, and see the terrain and procedural grass and stones update around the old and new footprints. Use Undo/Redo to restore both the object and terrain. In Play, the orange ball lands on the joined rock.

• Uses AdaEngine's existing meshlet selection for terrain LOD. The MVP adds one coarse level and keeps section boundary edges fixed. Wireframe and Shaded use the same selected triangles. Terrain with varying paint keeps full detail.
• Includes the Terrain v2 runtime and editor dependencies, the desktop Manifold authoring kernel, fixtures, and guide updates so the branch is self-contained.
• Open Mesh Terrain Workshop from this checkout.

Validation and draft status

• Workshop project validation returned zero diagnostics. Offline documentation, six SDK packaging tests on Linux/WSL, and the scoped Python checks passed.
• Before integration with current main, 13 targeted engine tests and 4 real WebGPU checks passed. The WebGPU tests include identical triangle selection in Shaded and Wireframe. Windows Studio and the exported Workshop were exercised in the editor and browser.
• The native Windows build compiled the engine and Mesh Terrain authoring kernel on this branch. The root headless test bundle failed to compile in the unchanged Render3DMeshletTests and Render3DPathTracingTests because WGSLShaderCompiler is unavailable there. An isolated run of the Mesh Terrain and shader reflection tests is in progress. Metal and the complete platform matrix are pending.
• The fast publication check reported 2,529 SwiftLint violations across 436 scanned Swift files and 105 secret-scanner findings. The flagged data was traced to vendored provenance digests, public revision pins, test constants, and serialized Workshop data. The repository scanner still reports these findings. The user authorized a one-time exception to the local contribution pre-push check for this draft. Git LFS validation still ran.
• The scope is the showable MVP. Independent review and the remaining authoring work are pending.

[chatgpt-codex-connector]

Codex Review Summary: ✅ Completed

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-11-07T19:29:05.086474Z	430ce5e	Draft marked ready

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review" or "@codex security review".

Codex reacts with 👀 while any review is running, comments if it has suggestions, and reacts with 👍 once all reviews finish with no findings.