Every 400, 403, 404 and 500 on an admin page now answers with an
error page in the normal layout: one fixed line for the status and a
link back to the webhook list, or to sign-in when nobody is signed
in. The router's handler for unknown paths and the CSRF middleware's
refusal use the same page. Status codes are unchanged. The receiver,
the healthcheck and /metrics keep their plain answers. If the error
page itself cannot render, the answer is the same status in plain
text.
Model: opus-5-5
