v1.5.1 — PyPI readme hotfix + unshipped-import cleanup

Patch release. No code / behaviour changes vs. v1.5.0. Every public signature is byte-for-byte identical to v1.5.0.

Fixed

• PyPI project-page broken image. The README's interactive plot editor screenshot used a relative path (./image-1.png) — GitHub resolved it fine but PyPI showed a broken-image icon. Both README.md and README_CN.md now use an absolute raw.githubusercontent.com URL so both renderers work.
• Broken import statspai on main between v1.5.0 and v1.5.1. Commit 8155ada (between the two tags) pre-wired v1.6 symbols — llm_dag_constrained, llm_dag_validate, LLMConstrainedDAGResult, DAGValidationResult, paper, PaperDraft, mr_lap, mr_clust, grapple, mr_cml — into the top-level package before their implementations landed. Any fresh git clone + pip install -e . between those tags raised ImportError. The shipped PyPI v1.5.0 wheel was not affected (it pre-dates 8155ada). v1.5.1 removes the premature imports; they will return in v1.6 alongside their implementations.

Changed

• README visual-weight fix. v1.5.0 section now carries a v1.5 Highlights table paralleling the v1.4 Highlights table below it, so the current release is the README's visual subject instead of being crowded out by the previous-version section. README_CN.md updated in lockstep.

Upgrade notes

If you installed v1.5.0 from PyPI, there is no functional reason to upgrade — the PyPI wheel was unaffected by the main-branch import bug. Upgrade only if you want the cleaner PyPI project page.

If you installed from source off main between v1.5.0 and v1.5.1, upgrading (or pulling v1.5.1) fixes the ImportError.

See CHANGELOG.md for the full entry.