Package for npm publish

[jorgeraad]

Sets surface up to be installed via npm install @pensar/surface and used as both a CLI and a typed library. Adds a tsup build (ESM, types, two entries), a fixture-based smoke test, and CI workflows for PR validation and tag-triggered publish.

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Note

Medium Risk
Medium risk because it changes the packaging/entrypoints (package.json exports/bin) and adds automated publish workflows, which can break installs or CLI execution if misconfigured.

Overview
Sets the project up to be published and consumed as @pensar/surface by switching to a built dist/ bundle with explicit exports, types, and CLI bin pointing to dist/cli.js (built via new tsup.config.ts).

Adds release safety rails: a post-build script that injects a Node shebang/exec bit for the CLI, a Node smoke test that imports dist/index.js and runs map() against a tiny Express fixture, and GitHub Actions workflows for PR CI and tag-triggered npm publish with provenance.

Includes supporting housekeeping (MIT LICENSE, README install/programmatic API docs, and ignores scripts/fixtures in Prettier).

^{Reviewed by Cursor Bugbot for commit 442e6c0. Bugbot is set up for automated code reviews on this repo. Configure here.}