Why: agents rediscovered Gitea hosts and credential locations from
scratch each session, and the retired git-panel host kept failing with
TLS broken-pipe errors before the right host was recalled.
Evidence: curl git-home...:30319/api/v1/version with token from
~/.secrets/gitea -> {"version":"1.27.3"}; ssh -p 31411 git@git-ssh...
(BatchMode) -> "Hi there, weichen!" with key ~/.ssh/home_gitea (ED25519,
SHA256:GYXaOXIMeloQ1fKSfdJ/ndgPQzs/Ix7Hk62ekfkfQ20). Same section already
merged in Agent-System-Dev (PR #73).
Impact: AGENTS.md only; records hosts and credential locations, no
secret values (baseline hard boundary 2).
Refs: Agent-System-Dev PR #73
weichen