Fixed one real inaccuracy (Gitea registry scope, Secret Distribution
path count) and replaced generic descriptions with true, specific
detail across all 14 Systems bullets - real incidents, real design
decisions, concrete numbers - each checked against Trilium and, where
relevant, the live Ansible roles rather than trusted at face value.
Also stages a verified-but-unintegrated PAM hardening finding in
docs/firewall-and-network.md for that file's own upcoming audit pass.