Deployment, Releases, Automation

[twi-exe]

This pull request introduces several improvements to the development workflow, documentation, and code quality for the retort-ai-extension project. The most significant changes are the addition of a GitHub Actions workflow to automate release artifact creation, expanded documentation for alternative installation and distribution methods, and updates to code linting and packaging scripts for better compatibility and maintainability.

Workflow and Release Automation:

• Added a new GitHub Actions workflow (.github/workflows/create_release.yml) that builds the extension, packages it as extension.zip, and attaches it to a GitHub Release, supporting both manual and automatic triggers.

Documentation Improvements:

• Added INSTALL.md with detailed instructions for installing and distributing the extension without the Chrome Web Store, including developer, GitHub Release, Firefox, and enterprise options.
• Updated README.md to include instructions for installing the extension from GitHub Releases and a step-by-step guide for adding the OpenRouter API key in the extension settings.

Build and Packaging Enhancements:

• Updated package.json:
  • Bumped version to 0.1.3 and added a description.
  • Added scripts for packaging (package), creating release artifacts, and Firefox compatibility (web-ext-build, web-ext-run).
• Added a sample package.json.new with metadata, keywords, and engine requirements for improved project setup and discoverability.

Linting and Code Quality:

• Improved ESLint configuration in eslint.config.js:
  • Explicitly included the chrome global for extension development.
  • Enhanced unused variable rule to ignore arguments starting with an underscore, reducing false positives.
• Updated background scripts (public/background.js, src/background.js) to ignore unused tab arguments by renaming them to _tab, aligning with linting rules.