Add Authentik SSO service and refactor Valkey configuration to use native tools and consolidated systemd service

roles/valkey/templates/valkey.conf.j2

@@ -31,7 +31,7 @@ tcp-keepalive {{ valkey_tcp_keepalive }}
 # =================================================================
 
 # Require password for all operations
-requirepass {{ valkey_requirepass }}
+requirepass {{ valkey_password }}
 
 # =================================================================
 # Memory Management
@@ -127,4 +127,4 @@ client-output-buffer-limit pubsub 32mb 8mb 60
 # - Database 3+: Future applications
 #
 # Connection example:
-# redis-cli -h {{ valkey_bind }} -p {{ valkey_port }} -a {{ valkey_requirepass }} -n 1
+# valkey-cli -h {{ valkey_bind }} -p {{ valkey_port }} -a {{ valkey_password }} -n 1