Rationale for this change

Closes #3064

Fix pyparsing warning on import of pyiceberg.table.Table

• Add a regression test that enables warn_ungrouped_named_tokens_in_collection and verifies the import path stays clean.
• Remove the parser results-name collision that triggered PyparsingDiagnosticWarning during from pyiceberg.table import Table.

Are these changes tested?

Yes. test fails before the fix commit, and succeeds after

manually verify with

make install
uv run --python 3.13 -- python -Werror -c "from pyiceberg.table import Table"

Are there any user-facing changes?