All docstrings, comments, log/notification strings, and markdown docs
translated to English across the codebase (27 files) — no functional
changes. Verified: py_compile on all Python files, a real --dry-run
against inFlow, and a smoke test of PDF rendering + Telegram listener
message logic, all clean after translation.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>