Fix same-line rank/PIB corruption; consistent surname stems; ending counts toward the half-limit (v3.0.14–3.0.16)

[click0]

Summary

Three fixes driven by a real counterexample:

was:  довідках №273 рядового МАЗУРЕНКА
got:  довідках №857 старшого рядового МАЗИДЕНКА

v3.0.14 — engine: several ranks / PIBs on one line no longer corrupt each other

Masks were substituted into the partially masked line with str.replace(original, mask, 1). When the mask of one rank contained the form of another rank on the same line (рядовий → старший солдат, солдат → рядовий), the second substitution hit the freshly inserted mask: рядового МАЗУРЕНКА та солдата КОВАЛЕНКА → старшого рядового МАЗИДЕНКА та солдата КОВИЛЕНКА (non-existent rank, second rank left unmasked, unmask restored the wrong rank). Replacements are now numbered placeholders in the working copy of the line, substituted once at the end. Same fix for full-name replacements. New tests: tests/test_same_line_replacement.py.

v3.0.15 — surname: one person, one synthetic stem

The synthetic stem was seeded from the surface form, so МАЗУРЕНКА / Мазуренка / Мазуренко got three unrelated masks. The seed is now the lower-cased stem; all letter-case and grammatical-case forms share one stem, and ending + case are applied on top. Unmask is mapping-driven and unaffected.

v3.0.16 — surname prefix: the preserved ending counts toward "at most half"

Only the prefix was capped at half the word, so with a long ending most of the original stayed visible (Мазуренка → Мазиденка: 7 of 9 letters). Prefix + preserved ending are now limited to half of the base form: Коваль → 3, Ґудзь → 2, Іванов → 1, Бондаренко → 1, Петренко → 0. Computed from the base form so all cases of one surname keep the same prefix. Docs, config template and tests updated.

Test plan

• pytest tests/ — 810 passed, 1 skipped
• mypy datamasking/ — 0 errors
• flake8 --select=E9,F63,F7,F82
• Manual: the counterexample line masks to старшого солдата … та рядового … and unmasks to the original
• CI green on the full matrix

🤖 Generated with Claude Code

https://claude.ai/code/session_01XT6iUWaQgahXDB9TWX9Bq7

---

Generated by Claude Code