fix(general_text): keep refined text in ReferenceRemoverRefiner output

[raams95]

Summary

ReferenceRemoverRefiner computes the cleaned text (with <ref> tags and {{cite ...}} templates removed) but then appends the original item to the output list. The result is that the operator never changes anything, and references are still in the output column.

ReferenceRemoverRefiner().run(storage, input_key="text")
# "Paris is the capital of France.<ref>Smith 2020</ref>" comes back unchanged

The "Total modified items" log was also off: numbers was incremented twice for each modified row.

Fix

Append refined_text instead of item, and drop the extra numbers += 1 so each modified row is counted once. Rows without references are returned as-is, same as before.

Tests

I added test/cpu_only/test_reference_remover_refiner.py. It runs the refiner on a small dataframe with a <ref> tag, a {{cite ...}} template and a plain row, then checks the output column.

• Before the fix: 1 failed (output equals the input)
• After the fix: 1 passed

pytest -m "cpu or api" test/cpu_only/test_reference_remover_refiner.py -q
1 passed

Fixes #554