Function convert_mesh_to_site_local 

pub fn convert_mesh_to_site_local(
    mesh: &mut MeshData,
    site_transform: Option<&Vec<f64>>,
)

Rotate a mesh into the site-local axis frame. Only runs for the site_local coordinate-space tier; translation alignment happens upstream via the router’s RTC subtraction.

pub only as public API surface: the claim that the streaming server calls it to rotate meshes produced outside this crate’s parallel loop was stale — a repo-wide search finds no caller outside this crate and its own integration tests. Kept pub because removing a re-exported item is a breaking change (#4192), not because anything downstream is known to need it.