testing: bootstrap UI, agent reliability, NS-01..04 + alert username

Smoothes the rough edges that came up exercising a live deployment.

First-run bootstrap UI: /bootstrap renders a username + password form
that uses the in-memory token directly (operator no longer copies it
out of the log); /login redirects there while bootstrap is available.

Agent reliability: failJob synthetic envelopes so command.run early
returns no longer hang the server-side job; runtime probe of restic
restore --help drives --no-ownership instead of version sniffing
(0.18.x had it removed). Server unit re-shaped: ProtectSystem=full
plus ReadWritePaths=/etc/restic-manager, no ProtectHome — restore
can now write anywhere a user might want.

Restore wizard: default target is /root/rm-restore/<job-id>/ with
clearer help text. Re-init confirm input uses .field (was .input,
which doesn't exist — text was invisible).

NS-01 host delete: store DeleteHost, admin-band /hosts/{id}/delete
with hostname-confirm danger zone, audit, FK cascade, live WS close.

NS-02 enrollment-token recovery: outstanding-tokens panel on
/hosts/new, regenerate (preserves attachments) and revoke handlers
+ audit, store-level ListOutstandingEnrollmentTokens and
DeleteEnrollmentToken.

NS-03 repo init / probe surface: migration 0020 adds
hosts.repo_status + repo_status_error; WS handler projects every
init job's outcome onto the host row (idempotent already-initialised
collapses to ready); creds-save resets status and dispatches a fresh
probe; /hosts/{id}/repo/probe retry endpoint with banner.

NS-04 dashboard live + sort + filter: query-string filter
(q/status/repo_status/tag/sort/dir), 5s htmx live poll mirroring the
alerts pattern with a localStorage live toggle, sortable column
headers, filter row + clear.

Alerts page: ack'd-by line resolves user_id ULID to username.

Compose.yaml ignored — host-specific.

web/templates/partials/alert_row.html

@@ -1,6 +1,7 @@
 {{define "alert_row"}}
 {{$a := .Alert}}
 {{$hostNames := .HostNames}}
+{{$usernames := .Usernames}}
 {{$filter := .Filter}}
 {{$status := alertStatus $a.ResolvedAt $a.AcknowledgedAt}}
 
@@ -81,7 +82,12 @@
       </form>
     {{else if eq $status "acknowledged"}}
       <span class="text-ink-fade" style="font-size: 11px;">
-        ack'd{{if $a.AcknowledgedBy}} by {{deref $a.AcknowledgedBy}}{{end}} · {{relTime $a.AcknowledgedAt}}
+        {{$ackedBy := ""}}
+        {{if $a.AcknowledgedBy}}
+          {{$id := deref $a.AcknowledgedBy}}
+          {{if index $usernames $id}}{{$ackedBy = index $usernames $id}}{{else}}{{$ackedBy = $id}}{{end}}
+        {{end}}
+        ack'd{{if $ackedBy}} by {{$ackedBy}}{{end}} · {{relTime $a.AcknowledgedAt}}
       </span>
       <form method="post" action="/alerts/{{$a.ID}}/resolve">
         {{if $qs}}<input type="hidden" name="qs" value="{{$qs}}">{{end}}