feat(docker): Swarm task awareness — replaced tasks, service crash loops, last task error

Milestone 465 "Swarm task awareness". Fixes three defects from the live MCP
review #4973:
- #5008 "Swarm task history read as live state"
- #5009 "Crash-loop detection is blind to Swarm services"
- #5011 "Swarm task errors are not captured"

Agent and ingest (agent 1.8.0):
- A manager's agent now reports each service's newest tasks: slot, node,
  desired and current state, Swarm's Err/Message, exit code and time.
- They are stored in docker_swarm_services.tasks_json (migration
  docker_010_swarm_tasks).

Swarm view (pure):
- A task container is "replaced" when Swarm set its task's desired state off
  `running`. Without the task on record, a newer or running task in the same
  slot decides.
- Replaced containers are no longer replicas or crashes.
- Each service gets, from the task records:
  - failures_1h and failures_24h (failed or rejected tasks);
  - crash_looping (Settings → Thresholds count);
  - last_error, in Swarm's own words.

MCP:
- New findings: swarm_service_crash_looping (critical) and swarm_task_failed
  (warning, on a healthy service with a failure in 24h).
- Down and degraded findings name the last task error.
- list_swarm_services carries the failure fields.
- Container rows mark swarm_replaced and give a replaced task no problems.

Web:
- The containers page swarm cards and the Swarm topology page show crash
  loops, recent failures and the last task error.
- The dashboard widget flags a crash loop, and its "failed (24h)" count no
  longer counts a rolling update's killed task.

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

plugins/docker/templates/docker/rows.html

@@ -26,9 +26,10 @@
   </div>
 </div>
 
-{# ── Swarm services: collapsed per-service, each replica labelled with its host.
-   Ghost replicas (tasks on nodes with no Steward agent) come from the managers'
-   placement data so the picture is cluster-complete. ──────────────────────── #}
+{# ── Swarm services: collapsed per-service, each current replica labelled with
+   its host (tasks Swarm replaced are left out). Ghost replicas (tasks on nodes
+   with no Steward agent) come from the managers' placement data so the picture
+   is cluster-complete. A failing service names Swarm's last task error. ───── #}
 {% if swarm_services %}
 <div class="card-flush" style="margin-bottom:1.5rem;">
   <div style="display:flex;align-items:baseline;gap:0.6rem;padding:0.5rem 0.75rem;border-bottom:1px solid var(--border);">
@@ -46,6 +47,7 @@
           {{ s.running }}/{{ s.desired }} running
         </span>
       </div>
+      {% with style="padding-left:1.1rem;margin-bottom:0.35rem;" %}{% include "docker/_swarm_failures.html" %}{% endwith %}
       <div style="display:grid;grid-template-columns:repeat(auto-fill,minmax(210px,1fr));gap:0.4rem;padding-left:1.1rem;">
         {% for r in s.replicas %}
         {% if r.ghost %}