fix(org-chart): improve auto connector contrast and test portability

examples/org-chart/verify-p5-4.mjs

@@ -1,13 +1,13 @@
+import { loadPlaywright, launchChromium } from '../../scripts/orgchart-browser-runtime.mjs';
 // Focused P5-4 checks. Does not replay P5-1B/P5-23 suites or performance timings.
 import fs from 'node:fs/promises';
 import { writeFileSync } from 'node:fs';
 import http from 'node:http';
 import path from 'node:path';
-import { fileURLToPath, pathToFileURL } from 'node:url';
+import { fileURLToPath } from 'node:url';
 const root = fileURLToPath(new URL('../../', import.meta.url));
 const output = path.join(root, 'test-results/org-chart-p5-4');
-const playwright = process.env.ORGCHART_PLAYWRIGHT_MODULE;
-const { chromium } = await import(playwright ? pathToFileURL(playwright).href : 'playwright');
+await loadPlaywright();
 const fixtures = Object.fromEntries(await Promise.all(['small', 'medium', 'large'].map(async size => [size, JSON.parse(await fs.readFile(path.join(root, `examples/org-chart/data-expanded-${size}.json`), 'utf8'))])));
 const fixed = JSON.parse(await fs.readFile(path.join(root, 'examples/org-chart/data-p1.json'), 'utf8'));
 const results = [], errors = [], measurements = [];
@@ -37,7 +37,7 @@ const server = http.createServer(async (request, response) => {
 await fs.mkdir(output, { recursive: true });
 await new Promise(resolve => server.listen(0, '127.0.0.1', resolve));
 const origin = `http://127.0.0.1:${server.address().port}`;
-const browser = await chromium.launch({ executablePath: process.env.ORGCHART_CHROME ?? 'C:/Program Files/Google/Chrome/Application/chrome.exe', headless: true });
+const browser = await launchChromium({ headless: true });
 const page = await browser.newPage({ viewport: { width: 1440, height: 1000 } });
 const track = p => { p.on('pageerror', e => errors.push(e.message)); p.on('console', m => { if (m.type() === 'error') errors.push({message:m.text(),location:m.location()}); }); };
 track(page);