feat: critical fixes + health API + webhook + attack reports

- Fix busy-wait loop in ServerGuardService (removed while(true))
- Fix sync blocking on async Future (use thenAccept instead of .get())
- Add startup banner with system info and config validation
- Add HealthService: /api/health, /api/health/live, /api/health/ready
- Add RequestLoggingFilter for HTTP request monitoring
- Add CorsConfig for cross-origin support
- Add WebhookService (Discord/Slack notifications)
- Add AttackReportService with HTML report generation
- New endpoints: /api/attacks/recent, /api/attacks/report, /api/webhook/test
- Upgrade Lombok 1.18.30 to 1.18.38 for Java 25+ compatibility

src/main/resources/application.yml

@@ -165,6 +165,14 @@ serverguard:
       require-engine-handshake: true
       handshake-ttl-seconds: 30
 
+  webhook:
+    enabled: false
+    discord-url: ${ALUER_WEBHOOK_DISCORD:}
+    slack-url: ${ALUER_WEBHOOK_SLACK:}
+
+  report:
+    dir: ./reports
+
 server:
   port: 8080