Type Alias ProgressPhase

ProgressPhase:
    | "headerParse"
    | "dataParse"
    | "geometry"
    | "sceneBuild"
    | "serialize"

The sequential phases of a model load, matching the phase split already measured by Statistics (parseTime / geometryTime) and the CI perf harness (perf.csv) so a progress report, a CLI run and a CI perf row are directly comparable. See conway issue #301.

The heavy interiors of 'geometry' (per-face tessellation, CSG, weld) are single opaque wasm calls with no interior progress — ticks happen at the per-product TS loop, so a hang localizes to one product.