Function compute_mesh_manifest 

pub fn compute_mesh_manifest() -> MeshManifest

Compute the mesh-output determinism manifest over FIXTURE_IFC at TessellationQuality::Medium (the byte-identity density).

Pins the LOCAL-FRAME output (per-element f64 origin + element-local f32 positions - the shipping wasm viewer path) by forcing local_frame_set_enabled_override(Some(true)) for the REST OF THE PROCESS: wasm already defaults ON, native defaults OFF, and equalizing the flag is what makes the two targets’ bytes comparable. The override is deliberately not restored (a concurrent test restoring it mid-compute would race), so only dedicated determinism test binaries should call this.