Accumulator name after `lp.realize_reduction` is intractable

[kaushikcfd]

Maybe the newly introduced accumulator variables should be tagged with some specifications or the naming must be standardized. In feinsum, I have to rely on internals of realize_redudction (cf https://github.com/kaushikcfd/feinsum/blob/87e3a43dff6ebbc3709a3afc9df174ab2e12c8fa/src/feinsum/tuning/impls/ifj_fe_fej_to_ei.py#L447-L448) making the transformation fragile for long-term storage.

[inducer]

I think a tag on the variable would be the cleanest solution. PRs welcome.