## What this does
Polish + bug-fix pass on the Errors page so it can ship to everyone.
Touches the Slack alert config UX, errors list, error detail page, and
unhides the SideMenu entry for non-admins.
## Decisions
**"No channel" item over standalone Remove button**
Chose pinning a `<XMarkIcon /> No channel` `SelectItem` above the
channel list. Rejected the standalone "Remove channel" link in a
`<Hint>` — color/hover behaviour clashed with the sibling `<TextLink>`,
and "channel selection" is the right context for clearing. Server action
already deletes the channel when `slackChannel=""` is submitted.
**Slack `<!date^>` token over per-user TZ field for alerts**
Chose Slack's native `<!date^TS^…>` token so each viewer sees timestamps
in their own timezone (UTC fallback). Rejected per-user/per-org TZ
schema work — works for multi-region channels for free. Email/dashboard
TZ source-of-truth filed as TRI-8885 / TRI-8886.
**Make errors GA**
DKP
19c16759f6