[zhouaihui]

Outcome

PR and branch CI now runs source quality checks and the existing CPU/offline contract suite without building distributions. A separate Build release workflow builds and audits sdist/wheel artifacts, verifies checksums, and exercises wheel installation when a v* tag is pushed. The tag must exactly match v plus the package version before building.

The build and installation checks retain their existing commands and read-only repository permissions. Build and quality tools use isolated venvs. Contributor and release documentation describe the triggers, validation requirements, and Actions artifact handling; the workflow does not publish a GitHub Release or to PyPI.

Verification

• Passed actionlint 1.7.12 for both workflows (without optional ShellCheck/Pyflakes integration), YAML parsing, bash -n on all run blocks, local Markdown file-link checks, and git diff --check.
• Compared the split workflows with the original: CPU contract job and wheel installation steps are preserved, along with lint, compile, documentation, build/audit, and artifact upload commands.
• Hosted PR CI run 42174765827 targeted commit 75ee7bdfe5dc5816e1161aaaa2efd7979cf88a66 and selected only quality and cpu-contract-tests. Both jobs failed before starting because GitHub reported failed account payments or an insufficient spending limit. No source checks or tests executed; rerun after the billing restriction is resolved. No release-build run was triggered by this PR.
• Tag-triggered build and installation remain unverified: no tag has been pushed. No GPU/runtime acceptance is claimed; this change only reorganizes workflows and documentation.

Compatibility and provenance

• No runtime, public configuration, checkpoint, or export changes. The quality job check name changes from quality-and-package to quality.
• Existing ASpec workflow steps were moved; no new upstream code or license-text changes.