feat: uniform system.content source schema across installers and repositories

roles/bootstrap/vars/main.yml

@@ -314,7 +314,6 @@ bootstrap_archlinux:
     - nfs-utils
     - ppp
     - python
-    - reflector
     - rsync
     - sudo
     - tldr
@@ -327,5 +326,6 @@ bootstrap_archlinux:
       (['openssh'] if system_cfg.features.ssh.enabled | bool else [])
       + (['iptables-nft'] if system_cfg.features.firewall.toolkit == 'nftables' and system_cfg.features.firewall.enabled | bool else [])
       + (['sbctl'] if system_cfg.features.secure_boot.enabled | bool else [])
+      + (['reflector'] if system_cfg.content.url | length == 0 else [])
       + (bootstrap_common_conditional | reject('equalto', 'nftables') | list)
     }}