Fix VibeDev end-to-end: ESLint v9 config, working lint, health endpoint smoke test in CI

[Copilot]

The CI lint step was silently no-oping (ESLint v9 requires a flat config file, none existed), and CI had no actual server health check — only import-level smoke tests.

Changes

• eslint.config.js — New ESLint v9 flat config covering server/**/*.js and client/src/**/*.{js,jsx}. Includes proper globals for Node 18 (native fetch, URL, etc.) and React plugin rules.
• package.json — Added @eslint/js to devDependencies.
• .github/workflows/ci.yml:
  • Lint step: npx eslint server/ — v9 syntax, --ext flag removed, || true bypass removed so lint failures are now visible.
  • Added Smoke-test health endpoint step: starts the server, waits, curls /api/health, asserts HTTP 200, then kills the process.

- name: Smoke-test health endpoint
  run: |
    node server/index.js &
    SERVER_PID=$!
    sleep 3
    STATUS=$(curl -s -o /dev/null -w "%{http_code}" http://localhost:4000/api/health)
    kill $SERVER_PID 2>/dev/null || true
    if [ "$STATUS" != "200" ]; then
      echo "❌ Health endpoint returned HTTP $STATUS"
      exit 1
    fi
    echo "✅ Health endpoint returned HTTP 200"

[Copilot]

Pull request overview

This PR aims to make CI enforcement real end-to-end by introducing an ESLint v9 flat config, ensuring the server lint step actually fails on violations, and adding a CI smoke test that starts the backend and checks the /api/health endpoint.

Changes:

• Add a new ESLint v9 flat config (eslint.config.js) covering server JS and client JS/JSX.
• Update dependencies/lockfile to support the ESLint v9 config.
• Update CI to run server lint without bypassing failures and to smoke-test the health endpoint.

Reviewed changes

Copilot reviewed 3 out of 4 changed files in this pull request and generated 3 comments.

File	Description
package.json	Adds ESLint config dependency (but currently with dependency scope/version inconsistencies).
package-lock.json	Lockfile updates reflecting the dependency changes.
eslint.config.js	Introduces ESLint v9 flat config for server + client with React/React Hooks rules.
.github/workflows/ci.yml	Makes lint blocking and adds a backend /api/health smoke test step.

Suppressed comments (1)

package.json:44

• @eslint/js is duplicated across dependencies and devDependencies, and the versions differ (^10.0.1 vs ^9.22.0). This can lead to unexpected resolutions and potential incompatibility with ESLint 9. Keep a single @eslint/js entry in devDependencies and align it with the ESLint major version.

  "devDependencies": {
    "eslint": "^9.22.0",
    "eslint-plugin-react": "^7.37.4",
    "eslint-plugin-react-hooks": "^5.2.0",
    "prettier": "^3.5.3",
    "@eslint/js": "^9.22.0"
  },

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