[QUALITY] Fix broken lint infrastructure - ESLint missing from devDependencies

[Shooksie]

Problem

The npm run lint command is broken and fails with sh: eslint: command not found.

Root Cause

• package.json defines a lint script: "lint": "eslint src/"
• ESLint is NOT installed as a devDependency
• No .eslintrc configuration file exists

Current Status

$ npm run lint
> @launchapp/design-system@0.1.0 lint
> eslint src/

sh: eslint: command not found
Exit code: 127

Impact

• No automated code quality checks in development or CI
• No linting in CI/CD (no lint workflow in .github/workflows/)
• Code style violations and potential bugs go undetected

Solution

1. Install ESLint and related packages
2. Create .eslintrc.json configuration
3. Verify: npm run lint completes without errors
4. Add GitHub Actions linting workflow

Audit Date

2026-03-20 (Quality audit after 87 merged PRs in 7 days)