v0.7.3

Fix the patch_revisor section-target resolution bug surfaced by
the v0.7.2 live re-validation on paper 7f4f2363. The drafter
got a paper all the way through to the revision phase (v0.7.0's
verify_numbers parser fix worked), but the patch_revisor emitted
edits targeting canonical section names (section:results,
section:mechanism) that didn't exist in the actual draft. The
merger reported "target region not found" with no hint and the
paper REJECTED on parser bugs, not real hallucinations — for the
second release in a row.

Lane A — Pipeline

• Merger emits "did you mean..." suggestions on section/table
  not-found. When apply_edit can't resolve a section: or
  table: target, the error message now appends the list of
  available section titles or labelled tables in the document.
  Example before/after:
  • Before: target region 'section:results' not found in document
  • After: target region 'section:results' not found in document (available sections: 'Introduction', 'Identification Strategy', 'Empirical Strategy', 'Discussion')
    Two new public helpers: list_section_titles(text) and
    list_table_labels(text). Suggestions are suppressed when the
    list is empty (avoids the misleading
    (available sections: ) suffix on minimal LaTeX skeletons).
    Universal targets (paper:full / abstract / references)
    don't get suggestions.
• writing/scoped-revision.md skill update. New section
  ("Before you compose any edits — list the draft's actual
  targets") instructs the patch_revisor to grep the draft for
  \section{...} and \label{tab:...} lines before composing
  patches. Explains the case-insensitive substring matching the
  merger uses, the common failure mode (canonical-name vs
  actual-heading mismatch), and the paper:full fallback for
  findings that don't have a dedicated section.

Test counts

• Mocked suite: 598 passed (was 590 in v0.7.2; +8 here).
• 8 new tests in tests/pipeline/test_patch_merger.py:
  • 4 for list_section_titles and list_table_labels helpers.
  • 4 for the extended error: section suggestions, table
    suggestions, no suggestion for non-section/table targets, no
    misleading suffix when the list is empty.