v1.5.7 — Windows cp1252 decode fix

Field-fix release. v1.5.6 hardened the encode side (writing Cyrillic / ✓ output on Windows); v1.5.7 fixes the decode side — hooks and gates that read TAUSIK CLI or git output back.

Fixed

• SessionStart hook (and other CLI readers) crashed on Windows when captured output contained Cyrillic. subprocess.run(..., text=True) decoded child stdout with the OS locale codec (cp1252 on a typical RU Windows), which chokes on UTF-8 Cyrillic bytes (0x81 is undefined in cp1252). The reader thread raised UnicodeDecodeError, leaving result.stdout=None, then .strip() raised AttributeError outside the caught tuple — so the whole hook aborted with a traceback and no session context was injected (framework "silently broken" on Cyrillic-content projects). Every text=True subprocess reader of CLI/git output now passes encoding="utf-8", errors="replace" — 12 call sites across session_start, _common, auto_format, task_done_verify, session_metrics, check_docs, project_cli_extra, project_cli_renar, pytest_test_count, service_session, verify_git_diff. The last two also affect the task done / verify gates on repos with Cyrillic filenames or git user.name.

Full suite: 4313 passed / 12 skipped.