[P4suta]

Summary

Run fast Linux checks on every pull request and merge group.
Select native execution, API, packaging, and proof layers by their affected inputs.
Require every selected job to succeed.
Remove duplicate main checks, scheduled CodeQL, and unconditional hosted campaigns.
Keep protected release checks and local investigation commands.

Preserve Rust 1.84 compatibility and constrain sha2 to its compatible line.
Share the API nightly between installation and snapshot generation, and refresh the snapshot's rustdoc rendering.
Include compatible action updates from #30.
Run Windows-only doctests on Windows and keep supported Linux test targets.
Generate a short README, matching About description, and documentation links under the existing license grants.

Closes #53.

Validation

• Windows 11 Pro 10.0.26300, Rust 1.99.1: formatting, strict Clippy, repository laws, native tests, doctests, documentation, and API checks passed.
  Compilation for x64, i686, and ARM64 passed.
  Packaging, dependency policy, just reuse, and typos passed.
• Rust 1.84.1: workspace tests and doctests passed, including native parser, environment, ownership, and lifecycle regressions.
• Pinned Rust 1.99.1 Linux container: formatting, Clippy, laws, supported tests, empty-API compilation, dependency policy, just reuse, typos, and actionlint passed.
• The required gate passed 2,048 selections with failure, cancellation, missing-result, invalid-flag, and malformed-proof controls.
  Real path-filter and shell rejection checks passed.
• Renovate's strict validator, tool extraction, and package-rule checks passed.
• The README example ran with the published windows-spawn 0.1.0 crate.
  Metadata checks, actionlint, offline zizmor, and gitleaks passed.

Checklist

• Relevant local checks, including applicable just ci components, passed.
• Deterministic selection and rejection controls passed.
• Documentation covers the verification contract and preserves native ownership, safety, and cleanup contracts.
• API compatibility and the refreshed snapshot match the supported toolchain.
• Secret checks passed.
• Scope and documentation match the issue.

@coderabbitai ignore