SWWAF_ADMIN_TOKEN, or its _FILE form, opens GET and POST
/_smallwebwaf/bans, DELETE /_smallwebwaf/bans/<client> and GET
/_smallwebwaf/clients/<ip>. Unset, they answer 404; a missing or wrong
token gets 401, in observe mode too. They go through every check, as
the metrics do. POST takes a netblock or a client's address, a duration
or permanent, and a reason, and makes an admin ban even while another
lasts. DELETE lifts every active ban covering the address, kept and
marked lifted. Bans come back as bans.json entries; a client as
clients.json holds it, with its bans.
Judgement call: answers leave out bans.json's version field.
Judgement call: DELETE takes an address, not a netblock.
Rule suppressed: gosec G304 on a test reading bans.json.
Model: opus-5-5
