Add Airflow and Kafka broker configs to git

- config/airflow/airflow.cfg (fernet/API keys redacted) + live DAG sync
- config/kafka/kraft-server.properties (live KRaft broker on kafka01)
- Extend collect-fleet-config.sh for airflow/kafka collection
- Add docs/recommendations.md with prioritized next steps

config/airflow/README.md

@@ -1,14 +1,35 @@
-# Airflow
+# Airflow — atc-airflow01
 
-| Bestand | Beschrijving |
-|---------|--------------|
-| `airflow.cfg` | Referentie-configuratie (deploy naar Airflow home op lake01) |
-| `generate_data_dag.py` | DAG voor demo data-generatie |
+| Item | Value |
+|------|-------|
+| Host | `atc-airflow01` / `10.0.21.55` |
+| URL | http://atc-airflow01:8080/ or http://10.0.21.55:8080/ |
+| Home | `/root/airflow/` |
+| Config | `/root/airflow/airflow.cfg` |
+| DAGs | `/root/airflow/dags/` |
+| DB | SQLite (`airflow.db` — not in git) |
 
-## URL
+## Files in git
 
-http://atc-lake01.dell-atc.lan:8080/ (of `10.0.21.55:8080` volgens netwerk)
+| File | Notes |
+|------|-------|
+| `airflow.cfg` | Reference copy; `fernet_key` and `internal_api_secret_key` redacted |
+| `generate_data_dag.py` | Synced from live DAGs folder |
+| `../airflow/airflow.cfg` | Older path (legacy); prefer this directory |
 
-## Deploy
+## Restore
 
-Kopieer `generate_data_dag.py` naar de Airflow `dags/` folder op de lake-host en herstart de scheduler/webserver.
+```bash
+# On atc-airflow01
+mkdir -p /root/airflow/dags
+cp airflow.cfg /root/airflow/
+cp generate_data_dag.py /root/airflow/dags/
+# Set real fernet_key in airflow.cfg or via env
+systemctl restart airflow-webserver airflow-scheduler  # if using systemd
+```
+
+## Refresh
+
+```bash
+./scripts/collect/collect-fleet-config.sh
+```