feat(tickets): open, comment and resolve tickets from the UI and MCP; known issues on alerts and anomalies (#6351, #6352)

A ticket records a known problem: title, area, hosts, subject, description,
links to alert rules and anomalies, and a log of comments, edits, resolving
and reopening. Opening, resolving (with the resolution as the note) and
reopening go on the timeline; every step is audited, and the audit rows stay
off the timeline.

An alert or anomaly an open ticket covers (by link, by subject, or a
host-wide ticket on the host itself) shows a Known issue badge, and offers
"Open a ticket" prefilled from its rule or anomaly when none does. Hosts,
monitors and containers get a Known issues card.

MCP: list_tickets, get_ticket (viewer); open_ticket, update_ticket,
comment_ticket, resolve_ticket, reopen_ticket (operator). list_alerts and
list_anomalies carry known_issue; get_overview, get_host, get_monitor and
get_container carry open_tickets. Also update_change and delete_change for
changes recorded by hand (author or admin).

Tickets are left out of backups, like the timeline (2026-10-15 ruling).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

steward/core/anomalies.py

@@ -17,7 +17,7 @@ What the operator ruled (System 182 "Metric Norms and Anomalies"):
 """
 from __future__ import annotations
 
-from dataclasses import dataclass
+from dataclasses import dataclass, field
 from datetime import datetime, timedelta, timezone
 
 from sqlalchemy import ARRAY, String, bindparam, case, delete, func, or_, select, text, update
@@ -276,6 +276,8 @@ class AnomalyView:
     anomaly: MetricAnomaly
     last_span: MetricAnomalySpan | None
     href: str | None = None
+    # Open tickets that make it a known issue (tickets.service.known_issues).
+    tickets: list = field(default_factory=list)
 
     @property
     def ongoing(self) -> bool:
@@ -317,6 +319,10 @@ async def views(session, rows: list[MetricAnomaly], *, links: bool = True) -> li
         if links and key not in hrefs:
             hrefs[key] = await resource_url_for(session, *key)
         out.append(AnomalyView(a, latest.get(a.id), hrefs.get(key)))
+    from steward.tickets.service import known_issues
+    known = await known_issues(session, {a.id: ([("anomaly", a.id)], a.resource_name) for a in rows})
+    for v in out:
+        v.tickets = known.get(v.anomaly.id, [])
     return out