Move standalone repository docs from the root into docs/ and add a documentation index that links the moved docs and the code-local runbooks.
Update Markdown links, source comments, and the root entry points to the new locations. Keep README.md and AGENTS.md at the root as required entry points.
Assisted-by: DeepSeek Harness (deepseek-flash)
No host defines a *-nixos-tests output; the pod firewall drops 5900-5903
from pod sources; the mihomo core keeps geodata and cache in its
StateDirectory; WA-020 was used twice and the cited WA-028 had no row.