Add Main Street Tutorial scenario, non-interactive overlays, smoke test, and fix build #53

	# PR quality gates: fast test + build check on every pull request.
	# Uses a reduced Monte Carlo seed count (MONTE_SEEDS=20) for quick feedback.
	# The main branch deploy workflow runs the full harness (MONTE_SEEDS=200).
	name: PR Checks

	on:
	pull_request:
	branches: [main]

	permissions:
	contents: read

	jobs:
	test-and-build:
	runs-on: ubuntu-latest

	steps:
	- name: Checkout
	uses: actions/checkout@v4

	- name: Setup Node.js
	uses: actions/setup-node@v4
	with:
	node-version: 20
	cache: npm

	- name: Install dependencies
	run: npm ci

	- name: Install Playwright Chromium
	run: npx playwright install chromium

	- name: Run tests (reduced Monte Carlo seeds)
	run: npm test
	env:
	MONTE_SEEDS: 20
	MONTE_MIN_WIN_RATE: 0.20
	MONTE_MAX_WIN_RATE: 0.80

	- name: Build
	run: npm run build

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