按建议，继续完成后续工作

结论：arc_semantics 已纳入 upstream rs274 side-by-side fixture baseline，ARC_FEED 几何参数按 LinuxCNC rs274 输出精度标准化，完整 native probes 验证通过。

wasm-port/docs/drift-report.md

@@ -67,11 +67,11 @@ semantic rewrites:
   source.
 - Fixture expectations are checked against the standalone vendored source
   path. The upstream `rs274` side-by-side baseline now covers simple motion,
-  offsets, feed-control, comment/logging, numbered-parameter, probing,
-  spindle-orient, file-open reset, file-finish, tool-reload, and O-word
-  subroutine fixtures; it also covers threading/rigid tap, NURBS dispatch
-  boundaries, and comparable canonical runtime edge and program-end cleanup
-  calls. Adapter-heavy fixtures, standalone modal-state assertions, and
+  arc geometry, offsets, feed-control, comment/logging, numbered-parameter,
+  probing, spindle-orient, file-open reset, file-finish, tool-reload, and
+  O-word subroutine fixtures; it also covers threading/rigid tap, NURBS
+  dispatch boundaries, and comparable canonical runtime edge and program-end
+  cleanup calls. Adapter-heavy fixtures, standalone modal-state assertions, and
   upstream `rs274` output gaps such as `WAIT` or hidden NURBS control-point
   detail still need dedicated native LinuxCNC baselines.