Export programmatic API for spec-ci-plugin

[hermanngeorge15]

Problem

The published package only exposes a CLI entry point. dist/index.d.ts exports nothing. Tool #4 (spec-ci-plugin) needs to consume the lint engine programmatically:

import { lint, allRules } from '@unityinflow/spec-linter';

Proposal

Add a separate library entry point (e.g. src/lib.ts) that exports:

• lint() from engine.ts
• allRules from rules/index.ts
• All types from types.ts
• parseSpecFile() from parser.ts

Update tsup to have two entry points: src/index.ts (CLI) and src/lib.ts (library).

Acceptance Criteria

• import { lint, allRules } from '@unityinflow/spec-linter' works
• Types are exported correctly
• CLI still works unchanged
• package.json exports field configured

Labels

enhancement, v0.1.0, dependency:spec-ci-plugin