Finalize v0.2 offline and release contracts - #6

Summary

• make --offline a zero-network contract across train, benchmark, eval and adapter export
• resolve and validate one pinned Hub adapter snapshot, then load that exact local directory with PEFT
• preserve zero-network PEFT auto-detection across Transformers 4.51.x and 5.x
• build release distributions once, publish and verify the same artifacts, and create GitHub Releases only after public PyPI verification
• correct pending Trusted Publisher and release-state documentation without changing scientific results

Final evidence

• complete CPU suite: 1004 passed, 5 deselected
• CUDA suite: 5 passed, 1004 deselected on RTX 4080
• focused offline contract: 129 passed, including socket denial and actual offline CLI train/benchmark/eval/export runs
• independent Transformers 4.51.3 and 5.14.1 environments: 124 passed each
• ruff and formatting clean; mypy clean over 73 source files; actionlint 1.7.12 accepts release.yml
• isolated wheel and sdist pass twine check; clean core wheel has no torch; clean [train] wheel completes demo/inspect/report
• package/schema/SVG/privacy/release checks: 88 passed; local and external Markdown link audits pass
• frozen benchmark SHA-256 remains 53fc1d4d5b7adee09618d77ad62d4086ba56b78569832d6fc7c3bcd5c2695bbc

No tag or publication will be created: PyPI pending publisher not yet registered remains the sole external blocker.