ci: Add conventional commits enforcement and auto-versioning

[rhoades-brown]

Summary

Adds conventional commit enforcement via a husky commit-msg hook and automated semantic versioning in CI.

Changes

Conventional commits (husky hook)

• Added husky devDependency with prepare script
• Created .husky/commit-msg hook validating commit messages match type(scope)?: description
• Allowed types: feat, fix, chore, docs, style, refactor, perf, test, build, ci, revert

Auto-versioning CI workflow

• Split ci.yml into build (lint/build/test) and release (version bump + GitHub release) jobs
• Release job analyses commits since last tag to determine bump type
• Bumps version in manifest.json, package.json, and versions.json
• Commits with [skip ci] to prevent infinite loops
• Creates GitHub release with main.js, manifest.json, styles.css attached
• Removed PR pre-release step

version-bump.mjs

• Added --bump=major|minor|patch CI mode

Documentation

• Created DEVELOPMENT.md with build/contributing/versioning docs
• Refactored README.md to point to DEVELOPMENT.md