feat: three major improvements - stable sources, archival, email alerts

1. Focus on Stable International/Regional Sources
   - Improved TED EU scraper (5 search strategies, 5 pages each)
   - All stable sources now hourly (TED EU, Sell2Wales, PCS Scotland, eTendersNI)
   - De-prioritize unreliable UK gov sites (100% removal rate)

2. Archival Feature
   - New DB columns: archived, archived_at, archived_snapshot, last_validated, validation_failures
   - Cleanup script now preserves full tender snapshots before archiving
   - Gradual failure handling (3 retries before archiving)
   - No data loss - historical record preserved

3. Email Alerts
   - Daily digest (8am) - all new tenders from last 24h
   - High-value alerts (every 4h) - tenders >£100k
   - Professional HTML emails with all tender details
   - Configurable via environment variables

Expected outcomes:
- 50-100 stable tenders (vs 26 currently)
- Zero 404 errors (archived data preserved)
- Proactive notifications (no missed opportunities)
- Historical archive for trend analysis

Files:
- scrapers/ted-eu.js (improved)
- cleanup-with-archival.mjs (new)
- send-tender-alerts.mjs (new)
- migrations/add-archival-fields.sql (new)
- THREE_IMPROVEMENTS_SUMMARY.md (documentation)

All cron jobs updated for hourly scraping + daily cleanup + alerts

test-ted-selectors.mjs

@@ -0,0 +1,32 @@
+import { chromium } from 'playwright';
+
+const browser = await chromium.launch({ headless: true });
+const page = await browser.newPage();
+
+const url = 'https://ted.europa.eu/en/search/result?q=&page=1&placeOfPerformanceCountry=GBR';
+console.log('Loading:', url);
+
+await page.goto(url, { waitUntil: 'networkidle', timeout: 30000 });
+await page.waitForTimeout(3000);
+
+// Save screenshot
+await page.screenshot({ path: '/tmp/ted-screenshot.png', fullPage: false });
+console.log('Screenshot saved to /tmp/ted-screenshot.png');
+
+// Get page HTML sample
+const bodyHTML = await page.evaluate(() => {
+  return document.body.innerHTML.substring(0, 5000);
+});
+
+console.log('\nFirst 5000 chars of body HTML:');
+console.log(bodyHTML);
+
+// Try to find any links to notices
+const noticeLinks = await page.evaluate(() => {
+  const links = Array.from(document.querySelectorAll('a[href*="/notice/"], a[href*="Notice"]'));
+  return links.slice(0, 5).map(a => ({ href: a.href, text: a.textContent.trim().substring(0, 100) }));
+});
+
+console.log('\nFound notice links:', JSON.stringify(noticeLinks, null, 2));
+
+await browser.close();