125 shims carried private copies of the same small helpers (put_vec, st,
nl_status, Rd, dump_crv, read_nurb, ...). Move the most common, byte-identical
form of each into three headers grouped by the upstream API they need, and have
those shims pull them in with `using sc::<name>;`. Shims with a different
variant keep their own copy; files touched by open PRs are left alone.
`the_context()` stays per shim (its function-local SmContext must not be shared).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01FBLgPenT24P1dunqnZR1Dj
Adds the Rust port (surface::surface_cache::p2), the C++ shim, the ffi
wrapper, the difftest runner and fixtures. Wires the SmPlane override of
IsSingularity into the surface cache's Bezier approximation (p1).
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01FsWWaoeGNWKgzeGrF2Pkn5
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