Add healthchecks for Gramps celery and valkey services

DEPLOYMENT.md

@@ -17,7 +17,6 @@ Create these Docker secret files (all ignored by git):
 - `secrets/nextcloud_smtp_password.txt`
 - `secrets/nextcloud_redis_password.txt`
 - `secrets/passbolt_db_password.txt`
-- `secrets/gramps_db_password.txt`
 - `secrets/influxdb_init_password.txt`
 - `secrets/prometheus_kuma_basic_auth_password.txt`
 
@@ -31,7 +30,7 @@ chmod 600 secrets/*.txt
 
 These values were previously hardcoded and must be rotated in upstream systems immediately:
 
-- Database credentials (Nextcloud, Passbolt, Gramps, InfluxDB).
+- Database credentials (Nextcloud, Passbolt, InfluxDB).
 - Nextcloud SMTP app password.
 - Authelia reset JWT secret, session secret, storage encryption key.
 - Traefik CrowdSec LAPI key.