DO-NOT-MERGE · Remove leaked internal decision-log file from public repo root

[Antawari]

DO NOT MERGE — operator merges; do not auto-merge.

What

Removes code-synth-bon351.md from the repository root via git rm.

Why

This file was an internal code-synthesis verdict document that should never
have shipped to this public repository. It contained internal-only material
(tracker identifiers, internal worktree and branch paths, and deprecated
internal role vocabulary) and is not part of the published package surface.
The repository's own packaging audit already flagged it as a non-shipping,
root-level non-python artifact and recommended its exclusion; this PR
implements the removal.

The deletion is fully self-contained:

• not referenced by pyproject.toml (no include / force-include / exclude entry),
• not imported by any module,
• not read by any test.

The only remaining mention is the historical audit report under
docs/audit/scout-reports/, which documents the removal recommendation and is
intentionally left untouched as a historical record.

How to verify

git rm code-synth-bon351.md
test ! -e code-synth-bon351.md && echo DELETED
grep -rn 'code-synth-bon351' src tests pyproject.toml || echo 'no references'
python -m venv /tmp/bpv && /tmp/bpv/bin/pip -q install pytest
PYTHONPATH=src /tmp/bpv/bin/pytest tests/smoke -q

Gate results (run from the worktree)

• Deletion: DELETED confirmed; git status shows D code-synth-bon351.md only.
• References: no references in src/, tests/, pyproject.toml.
• Smoke suite (tests/smoke): 3 passed, 79 skipped, 7 xfailed, 56 xpassed, 0 failed.
• Lint (ruff check / ruff format --check on src/ + tests/) and pytest tests/
  are unaffected — only a root-level markdown file was removed; no src/ or
  tests/ files were touched.