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/mcp/tools/hosts.py

@@ -15,6 +15,7 @@ from steward.models.users import UserRole
 from ._shape import (
     age_s, bounded, clamp_limit, db_session, iso, lookback, pick, rnd, summarize,
 )
+from .tickets import open_tickets_for
 
 AGENT_SOURCE = "host_agent"
 
@@ -141,8 +142,9 @@ async def get_host(host: str, parts_limit: int = 20) -> dict:
 
     Returns the host's monitors (latest result, error, uptime), the agent's
     latest values, alerts currently pending, firing or acknowledged on this
-    host's resources, and the Ansible inventory target linked to it with its
-    groups (`ansible_target`: null when unlinked).
+    host's resources, its open tickets (`open_tickets`: known problems someone
+    recorded, list_tickets / get_ticket), and the Ansible inventory target
+    linked to it with its groups (`ansible_target`: null when unlinked).
 
     The agent's values are `agent.metrics` (host-level) and its sub-resources
     grouped by kind: `mounts` (fullest first), `interfaces` and `disk_io`
@@ -166,6 +168,7 @@ async def get_host(host: str, parts_limit: int = 20) -> dict:
             select(AnsibleTarget).where(AnsibleTarget.host_id == h.id)
             .options(selectinload(AnsibleTarget.groups))
         )).scalar_one_or_none()
+        tickets = await open_tickets_for(db, host=h.name)
 
     agent = None
     if samples:
@@ -218,6 +221,7 @@ async def get_host(host: str, parts_limit: int = 20) -> dict:
         ],
         "agent": agent,
         "active_alerts": alerts,
+        "open_tickets": tickets,
         "ansible_target": {
             "target_id": target.id,
             "target_name": target.name,