Add templates, tests, and miscellaneous project files

Includes new page templates (fitness-gym, nonprofit, online-course,
photography-studio, real-estate, startup-company, travel-blog,
wedding-invitation) with thumbnail SVGs, test specs, documentation
files, and minor updates to index.html, router.php, and playwright config.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

tests/debug-check.js

@@ -0,0 +1,17 @@
+const pw = require('playwright-core');
+(async () => {
+    const browser = await pw.chromium.launch({ headless: true });
+    const page = await browser.newPage();
+    const failed = [];
+    page.on('requestfailed', req => failed.push(req.url().substring(0,100)));
+    
+    await page.goto('/', {timeout:30000});
+    await page.waitForTimeout(15000);
+    
+    console.log('editor:', await page.evaluate(() => typeof window.editor));
+    console.log('grapesjs:', await page.evaluate(() => typeof grapesjs));
+    if (failed.length) console.log('Failed requests:', JSON.stringify(failed));
+    
+    await browser.close();
+    process.exit(0);
+})().catch(e => { console.error(e.message); process.exit(1); });