fix: resolve nightly analytics failure and optimize database connections

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Summary

• Fix daily aggregation scheduler that was failing at midnight (container scaled to 0)
• Optimize database connection pool to reduce page load latency
• Simplify container scaling to cron-only rules

Problem

1. Nightly analytics not running: The daily aggregation job was scheduled at midnight, but containers scale to 0 outside working hours (6:55 AM - 5:00 PM)
2. Slow page loads (7-10s): Azure PostgreSQL was dropping idle connections, causing reconnection delays on first request
3. Complex scaling rules: EventHub and HTTP scaling rules were ineffective with current configuration

Changes

Scheduler Alignment

• Move daily aggregation from 00:00 to 07:00 (Europe/Berlin)
• Ensures container is active when scheduler runs

Database Connection Optimization

• Add HikariCP keepalive settings (180s interval)
• Prevents Azure PostgreSQL from dropping idle connections
• Applied to: analytics-service, data-processor, notification-service

Simplified Scaling

• Remove EventHub scaling rules (redundant with cron rule + maxReplicas: 1)
• Remove HTTP scaling rules (cron already ensures availability during working hours)
• All services now use cron-only scaling: 6:55 AM - 5:00 PM Mon-Fri

New Warmup Endpoint

• GET /api/analytics/warmup - lightweight DB query for connection warmup
• Enhanced health checks with database status

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud