chore: add GitHub CI, release workflow, and contributor docs

[kundeng]

Summary

• Adds CI workflow (npm test + npm run build on PR/push to main)
• Adds tag-driven release workflow: on v*.*.* tag, packages dist/ as zip and attaches to a GitHub Release
• Adds issue/PR templates, CONTRIBUTING guide, and seeded CHANGELOG
• Release workflow enforces tag ↔ manifest.json version parity

Test plan

• CI job passes on this PR
• After merge, a dry-run tag (e.g. on a throwaway branch) exercises release workflow

🤖 Generated with Claude Code

Summary by CodeRabbit

• Documentation

  • Added installation and contributing guidelines for developers
  • Added changelog documenting project releases and features

• Chores

  • Established GitHub issue and pull request templates
  • Configured automated CI/CD workflows for testing and releases

[coderabbitai]

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Free

Run ID: 67c3f742-78bc-4a07-b4ef-54068f4e2ac4

📥 Commits

Reviewing files that changed from the base of the PR and between 425d357 and f60b19c.

📒 Files selected for processing (8)

• .github/ISSUE_TEMPLATE/bug_report.md
• .github/ISSUE_TEMPLATE/feature_request.md
• .github/PULL_REQUEST_TEMPLATE.md
• .github/workflows/ci.yml
• .github/workflows/release.yml
• CHANGELOG.md
• CONTRIBUTING.md
• README.md

---

📝 Walkthrough

Walkthrough

This PR adds GitHub workflows (CI and automated release), issue and pull request templates, and project documentation (CHANGELOG, CONTRIBUTING guide, and README updates) to establish development and release processes.

Changes

Cohort / File(s)	Summary
GitHub Workflows .github/workflows/ci.yml, .github/workflows/release.yml	CI pipeline for Node.js 20 testing on push/PR; release workflow with tag-based triggering, manifest version verification, zip packaging, and GitHub Release creation.
GitHub Templates .github/ISSUE_TEMPLATE/bug_report.md, .github/ISSUE_TEMPLATE/feature_request.md, .github/PULL_REQUEST_TEMPLATE.md	Standardized templates for bug reports, feature requests, and pull requests with structured sections and checklists.
Project Documentation CHANGELOG.md, CONTRIBUTING.md, README.md	Changelog with version history, contribution guidelines covering spec-driven workflow and development commands, CI badge and install instructions in README.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~12 minutes

Poem

🐰 Workflows in place, templates so neat,
Release pipelines making the workflow complete!
Docs guide us forward, on main we stay,
Automation hops in, hip-hip-hooray! 🎉

---

Note

🎁 Summarized by CodeRabbit Free

Your organization is on the Free plan. CodeRabbit will generate a high-level summary and a walkthrough for each pull request. For a comprehensive line-by-line review, please upgrade your subscription to CodeRabbit Pro by visiting https://app.coderabbit.ai/login.

_{Comment @coderabbitai help to get the list of available commands and usage tips.}