The IDENTIFIERS list in Tools/scripts/generate_global_objects.py is a slight burden

(This is partly inspired by gh-94706.)

In generate_global_objects.py, iter_global_strings() detects global strings by looking for _Py_ID() and _Py_DECLARE_STR() in the C source files. In some places those macros are used indirectly, which means the corresponding strings won't be detected by iter_global_strings().

Currently we manually add such strings to the IDENTIFIERS list at the top of the script. Before we added the discovery mechanism in iter_global_strings(), basically all the static strings were in this list. However, we found that there were several maintenance/development downsides to the manual list, so we added iter_global_strings(). At the time we didn't take the extra step of automating discovery of indirectly used names. We should address this.

CC @kumaraditya303

Start with Tools/scripts/generate_global_objects.py, focusing on iter_global_strings() and the manually maintained IDENTIFIERS list. Trace how the script scans C source files for _Py_ID() and _Py_DECLARE_STR(), then determine how indirectly used names can be discovered. Done means indirectly used global strings no longer require manual additions while generation remains correct.