gh-73487: Convert _decimal to use Argument Clinic (part 1) (#137606)

Co-authored-by: Adam Turner <[email protected]>

Author: skirpichev

Include/internal/pycore_global_objects_fini_generated.h

@@ -645,6 +645,7 @@ struct _Py_global_strings {
         STRUCT_FOR_ID(options)
         STRUCT_FOR_ID(order)
         STRUCT_FOR_ID(origin)
+        STRUCT_FOR_ID(other)
         STRUCT_FOR_ID(out_fd)
         STRUCT_FOR_ID(outgoing)
         STRUCT_FOR_ID(outpath)
@@ -704,6 +705,7 @@ struct _Py_global_strings {
         STRUCT_FOR_ID(return)
         STRUCT_FOR_ID(reverse)
         STRUCT_FOR_ID(reversed)
+        STRUCT_FOR_ID(rounding)
         STRUCT_FOR_ID(salt)
         STRUCT_FOR_ID(sched_priority)
         STRUCT_FOR_ID(scheduler)

Include/internal/pycore_global_strings.h

@@ -0,0 +1,3 @@
+Speedup processing arguments (up to 1.5x) in the :mod:`decimal` module
+methods, that now using :c:macro:`METH_FASTCALL` calling convention.  Patch
+by Sergey B Kirpichev.