refactor: extract OCR retry selection template reporting

[tryskian]

Summary:

• move OCR retry selection template report building/formatting into tools/manual_eval_ocr_retry_selection_template.py
• keep tools/manual_evals_db_health.py as the public CLI/facade import surface
• preserve the existing template schema/version and terminal formatting behaviour

Validation:

• ./.venv/bin/python3.14 -m ruff check tools/manual_eval_ocr_retry_selection_template.py tools/manual_evals_db_health.py tests/test_manual_evals_db_health.py tests/test_ocr_retry_local_executor.py
• ./.venv/bin/python3.14 -m unittest tests.test_manual_evals_db_health.ManualEvalsDbHealthTests.test_ocr_retry_selection_review_collapses_duplicate_source_artifacts tests.test_ocr_retry_local_executor.OcrRetryLocalExecutorTests.test_selection_template_terminal_output_hides_absolute_source_paths
• git diff --check
• make ci-python-style
• make type-check
• make lint-docs
• make package-install-check
• ./.venv/bin/python3.14 -m tools.manual_evals_db_health --ocr-retry-selection-template --json --limit 1
• make test