test(test-runner): migrate integration tests from mocha/chai to node:test

[bennypowers]

Summary

• Migrate shared integration/test-runner/ framework (7 test helper files, 567 lines) from mocha/chai to node:test/node:assert/strict
• Migrate test-runner-chrome, test-runner-playwright, test-runner-puppeteer test wrappers
• All four must migrate together since the wrappers import from the shared framework

Changes per component

integration/test-runner/ (shared framework):

• chai assertions to node:assert/strict
• Mocha globals (describe/before/it) to explicit node:test imports
• __dirname to import.meta.dirname
• Internal .js imports to .ts for strip-types compatibility
• Test script: mocha to node --experimental-strip-types --test

test-runner-chrome/playwright/puppeteer (wrappers):

• this.timeout(N) to describe('...', { timeout: N }, () => ...)
• ../src/index.js to ../dist/index.js
• Integration import uses .ts extension
• Test scripts: mocha to node --experimental-strip-types --test

No published code changes

All packages' src/ directories are untouched. Only test files and test scripts changed.

Test plan

• test-runner-chrome: 22/22 pass locally
• test-runner-puppeteer: 22/22 pass locally
• test-runner-playwright chromium: pass locally
• test-runner-playwright firefox: pass locally
• test-runner-playwright webkit: known local failure (missing system libs), passes in CI
• CI green

[changeset-bot]

⚠️ No Changeset found

Latest commit: c94513b

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