Improve PyRecEst backend contracts

[FlorianPfaff]

Summary

• tighten backend capability exports and public API contract coverage
• add docs, audit scripts, benchmark baselines, and scientific invariant coverage
• update CI/dependabot/nox configuration for the expanded checks

Validation

• Applied patch cleanly
• Ran poetry lock because pyproject.toml changed and committed the updated poetry.lock
• Checked for remaining .rej files and conflict markers
• Ran git diff --check
• Tests were not run per request

[github-actions]

✅⚠️MegaLinter analysis: Success with warnings

Descriptor	Linter	Files	Fixed	Errors	Warnings	Elapsed time
✅ COPYPASTE	jscpd	yes		no	no	26.79s
⚠️ MARKDOWN	markdownlint	3	0	14	0	0.83s
✅ MARKDOWN	markdown-table-formatter	3	2	0	0	0.51s
✅ PYTHON	black	7	4	0	0	2.7s
✅ PYTHON	isort	7	5	0	0	0.65s
✅ REPOSITORY	checkov	yes		no	no	32.01s
✅ REPOSITORY	gitleaks	yes		no	no	12.39s
✅ REPOSITORY	git_diff	yes		no	no	0.33s
✅ REPOSITORY	secretlint	yes		no	no	12.3s
✅ REPOSITORY	syft	yes		no	no	7.55s
✅ REPOSITORY	trivy-sbom	yes		no	no	4.14s
✅ REPOSITORY	trufflehog	yes		no	no	20.95s

Detailed Issues

⚠️ MARKDOWN / markdownlint - 14 errors

docs/backend-contracts.md:7:20 error MD060/table-column-style Table column style [Table pipe is missing space to the left for style "compact"]
docs/backend-contracts.md:7:28 error MD060/table-column-style Table column style [Table pipe is missing space to the left for style "compact"]
docs/backend-contracts.md:7:1 error MD060/table-column-style Table column style [Table pipe is missing space to the right for style "compact"]
docs/backend-contracts.md:7:20 error MD060/table-column-style Table column style [Table pipe is missing space to the right for style "compact"]
docs/scientific-validation.md:17:9 error MD060/table-column-style Table column style [Table pipe is missing space to the left for style "compact"]
docs/scientific-validation.md:17:19 error MD060/table-column-style Table column style [Table pipe is missing space to the left for style "compact"]
docs/scientific-validation.md:17:30 error MD060/table-column-style Table column style [Table pipe is missing space to the left for style "compact"]
docs/scientific-validation.md:17:1 error MD060/table-column-style Table column style [Table pipe is missing space to the right for style "compact"]
docs/scientific-validation.md:17:9 error MD060/table-column-style Table column style [Table pipe is missing space to the right for style "compact"]
docs/scientific-validation.md:17:19 error MD060/table-column-style Table column style [Table pipe is missing space to the right for style "compact"]
docs/scientific-validation.md:27:13 error MD060/table-column-style Table column style [Table pipe is missing space to the left for style "compact"]
docs/scientific-validation.md:27:25 error MD060/table-column-style Table column style [Table pipe is missing space to the left for style "compact"]
docs/scientific-validation.md:27:1 error MD060/table-column-style Table column style [Table pipe is missing space to the right for style "compact"]
docs/scientific-validation.md:27:13 error MD060/table-column-style Table column style [Table pipe is missing space to the right for style "compact"]

Notices

📣 MegaLinter 9.5.0 is out! Discover the new features and security recommendations in the release announcement. (Skip this info by defining SECURITY_SUGGESTIONS: false)

See detailed reports in MegaLinter artifacts
Set VALIDATE_ALL_CODEBASE: true in mega-linter.yml to validate all sources, not only the diff

Show us your support by starring ⭐ the repository

[github-actions]

Test Results

    10 files  ± 0      10 suites  ±0   2h 30m 49s ⏱️ - 1m 42s
 2 009 tests + 4   2 005 ✅ + 4      4 💤 ±0  0 ❌ ±0 
20 515 runs  +40  16 925 ✅ +40  3 590 💤 ±0  0 ❌ ±0 

Results for commit 2e1daaa. ± Comparison against base commit 346c3cb.

♻️ This comment has been updated with latest results.