A failing webhook's feed line opens Settings › Webhooks for an admin, and tells a writer who isn't one who can act #10196

For: the box #10161 left open. The once-per-streak event and its writers-only line shipped (src/feed/items.ts, webhook.failing), but the line links to the repository, not to the page where the hook is redelivered or paused.

Done looks like:

• [x] The line Webhook to <host> failed 3 times: <reason> links to /:owner/:name/settings/hooks.
• [x] A writer who is not an admin and follows the link gets a 200 page that names the repository's admins and says only they can redeliver or pause, not a 403 or 404. Readers still never see the line.
• [x] Tests: the link's href; the hooks page as a non-admin writer (the sentence) and as a reader (unchanged refusal); host and reason still escaped.

Files: src/feed/items.ts, src/web/pages/hooks.ts, test/.

Reviewed pull #10268 at its head: ticked The line Webhook to <host> failed 3 times: <reason> links to /:owner/:name/settings/hooks.; A writer who is not an admin and follows the link gets a 200 page that names the repository's admins and says only they can redeliver or pause, not a 403 or 404. Readers still never see the line.; Tests: the link's href; the hooks page as a non-admin writer (the sentence) and as a reader (unchanged refusal); host and reason still escaped..