feat: export versioner as package

[alxdca]

Depends on #73. This PR is part of a stack created with Aviator. ➡️ feat: export versioner as package #74 feat: add 3.2.0 support to versioner #73 WIP: 3.2.0 action #72 main

Summary

• expose the orbit versioner as a package entrypoint via main, types, and exports
• add a dedicated package build/prepack path with tsconfig.package-runtime.json
• decouple the versioner runtime from Hardhat by exporting runOrbitVersioner(...) and using ethers JsonRpcProvider

Why / Context

• this branch builds on top of feat/versioner-3.2.0 and makes that versioner logic consumable outside the repo's Hardhat runtime
• packaging the versioner keeps the CLI/docker path usable while enabling reuse as a JS/TS package
• to reduce the dependency surface, the versioner script no longer depends on Hardhat, which had only been used as a JSON-RPC provider

Test Plan

• yarn build:package
• Run yarn orbit:contracts:version with valid INBOX_ADDRESS and PARENT_RPC_URL
• Verify a consumer can import the built entrypoint from dist/scripts/orbit-versioner/orbitVersioner.js