Prepare v0.1.0 release

[kanuwrld]

What changed

• finalize changelog entries under 0.1.0;
• pin README Action example to immutable v0.1.0;
• clarify full-SHA pinning recommendation.

Release verification

• 15 unit tests passed
• RepoReady self-audit: 100/100
• wheel and source distribution built
• wheel installed in a clean virtual environment
• installed repoready command audited this checkout successfully

Closes #10.

After merge

Tag merge commit as v0.1.0. Tag-triggered release workflow will build and
attach wheel plus source archive to GitHub Release.

Risk

Low. Documentation and release metadata only.