feat(ci): Add GitHub Actions CI workflow to run tests

[Copilot]

No CI existed to run tests on pushes or pull requests. Adds .github/workflows/ci.yml to close that gap.

Changes

• .github/workflows/ci.yml — New workflow that:
  • Triggers on push and pull request to any branch
  • Sets up Lua 5.1 + LuaRocks (consistent with the existing deploy-luarocks.yml)
  • Installs busted locally via LuaRocks
  • Runs eval $(luarocks path) to expose the local bin, then executes busted

Original prompt

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This section details on the original issue you should resolve

<issue_title>Create GitHub Actions workflow for CI</issue_title>
<issue_description>Run tests on CI.</issue_description>

Comments on the Issue (you are @copilot in this section)

Custom agent used: PR Creator Agent
An agent creates PullRequests when assigned to an issue

• Fixes Create GitHub Actions workflow for CI #32

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[Copilot]

Pull request overview

This PR adds a GitHub Actions CI workflow to automatically run tests on push and pull request events, addressing the lack of automated testing infrastructure for the luarrow project.

Changes:

• Added .github/workflows/ci.yml with a test job that installs Lua 5.1, LuaRocks, busted, and runs the test suite