fb86a18988
A team with one Alertmanager per Kubernetes cluster could not tell at a glance where an incident started: the cluster was only a word inside the title. When an alert carries a `cluster` label, the queue rows, the incident page and the alerts list now show it as a chip in that cluster's colour, a stable pick from the existing six-colour palette. A queue row drops `cluster=...` from its title, since the chip says it, and the incident page keeps the full title. An incident has the label only when it is in Alertmanager's group_by, which is also what keeps two clusters' identical alerts apart: incidents are matched on the team and the groupKey, and the groupKey does not include external labels. The README has a section on the two settings (Prometheus externalLabels and group_by). The alerts list reads the label from the alert itself, so it shows the chip with only the external label. Web UI and docs only: no endpoint or JSON shape changed, so nothing to mirror in terdut-tui. Nothing changes for a team whose alerts have no cluster label.