Add automated release workflow with versioning, changelog, and npm publish guardrails

[David-patrick-chuks]

Summary

Set up a repeatable release workflow for versioning, changelog generation, and guarded npm publication.

Why this matters

A serious SDK needs repeatable release mechanics. Manual publishing does not scale well and increases the risk of inconsistent releases.

Scope

• Choose a release workflow approach.
• Add CI automation for release preparation and validation.
• Add changelog and version management process.
• Add guardrails around publish conditions.
• Keep maintainer workflow understandable.

Acceptance Criteria

• Release automation is defined and checked into the repo.
• Versioning and changelog process are documented.
• Publish guardrails are in place.
• Workflow is ready for maintainers to adopt when npm publication begins.

Dependencies

• Depends on Improve package export surface and publish-time validation checks #15