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NilPy: print() of a list prints the handle, not the elements

Found 2026-07-20 sweeping the one-char-string family for [[bug-a-nilpy-one-char-literal-through-ctor-str-param]].

Repro

print("a,b".split(","))    # pxx: 129948866053376   CPython: ['a', 'b']
xs = ["a", "b"]
print(xs)                  # same

Indexing and iterating the list are correct — only its print (i.e. its str() / repr()) is. The value printed is the TPyList instance pointer.

Fix sketch

print of a tyClass whose class is TPyList/TPyDict should call a pylib repr helper rather than falling through to the integer path. Python's repr quotes str elements (['a', 'b']) and recurses, so the helper wants the element's variant tag — the same runtime-tag dispatch pylen_v / pyord_v already use.

Silent, and it makes the most natural debugging line in Python useless.

Gate

make test + self-host byte-identical, test-nilpy green, and the repro matching CPython for: list of str, list of int, list of float, nested list, empty list, and a dict ({'k': 'v'}).

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