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/compatibility-validation.md

@@ -109,14 +109,14 @@ machine-session validation remain future work.
 
 The current fixture expectations validate standalone behavior against both the
 vendored LinuxCNC source path and an upstream `rs274` side-by-side baseline for
-parser/conversion, offsets, feed-control, comment/logging, numbered-parameter,
-probing, spindle-orient, file-open reset, file-finish, tool-reload, and O-word
-subroutine fixtures, plus threading/rigid tap, NURBS dispatch boundaries, and
-the comparable canonical runtime edge and program-end cleanup calls. Fixtures
-that depend on standalone-only runtime adapters, HAL/INI/tool table setup,
-upstream `rs274` output gaps such as `WAIT` or hidden NURBS control-point
-detail, or richer machine session state still need dedicated native LinuxCNC
-baselines.
+parser/conversion, arc geometry, offsets, feed-control, comment/logging,
+numbered-parameter, probing, spindle-orient, file-open reset, file-finish,
+tool-reload, and O-word subroutine fixtures, plus threading/rigid tap, NURBS
+dispatch boundaries, and the comparable canonical runtime edge and program-end
+cleanup calls. Fixtures that depend on standalone-only runtime adapters,
+HAL/INI/tool table setup, upstream `rs274` output gaps such as `WAIT` or hidden
+NURBS control-point detail, or richer machine session state still need
+dedicated native LinuxCNC baselines.
 
 The kinematics probes currently cover LinuxCNC identity/trivial kinematics,
 the switchable `5axiskins` XYZBCW bridge-mill model, and the TRT `xyzac`/`xyzbc`