Publish to npm as @nostrability/schemata-codegen

[alltheseas]

Summary

Publish schemata-codegen to npm so consumers can install it as a devDependency and run it via npx.

Why

Currently the only way to use schemata-codegen is to clone the repo and run it locally. This blocks:

• CI automation in consuming repos (e.g. nostr-watch drift detection: pnpm generate && git diff --exit-code)
• Easy adoption by app devs (npx @nostrability/schemata-codegen --schemas ... --all)
• Dependency management via Renovate/Dependabot (auto-bump when codegen publishes a new version)

What's needed

1. Add bin field to package.json pointing to dist/index.js
2. Ensure files field includes dist/ and package.json
3. Add shebang (#!/usr/bin/env node) to CLI entry point
4. npm publish --access public
5. Verify npx @nostrability/schemata-codegen --help works

Effort: Low | Impact: High

This is a prerequisite for the nostr-watch integration (#8) and any CI automation in consuming projects.