Aggiunge monitoraggio ops: health check, log scanner, dashboard e notifiche.

Introduce incidenti con dedup, job Sidekiq ogni 3 min, scan log cron, /up/deep,
dashboard /admin/ops e push ntfy; include Sentry opzionale e fix test suite.

Co-authored-by: Cursor <cursoragent@cursor.com>

backend/app/services/ops/incident_recorder.rb

@@ -0,0 +1,67 @@
+module Ops
+  class IncidentRecorder
+    COOLDOWN = -> { ENV.fetch("OPS_NOTIFY_COOLDOWN_MINUTES", "30").to_i.minutes }
+
+    class << self
+      def record(finding)
+        new.record(finding)
+      end
+
+      def resolve(fingerprint:)
+        new.resolve(fingerprint: fingerprint)
+      end
+    end
+
+    def record(finding)
+      fingerprint = finding[:fingerprint] || fingerprint_for(finding)
+      incident = Ops::Incident.open.find_by(fingerprint: fingerprint)
+
+      if incident
+        incident.occurrence_count += 1
+        incident.last_seen_at = Time.current
+        incident.title = finding[:title] if finding[:title].present?
+        incident.message = finding[:message] if finding[:message].present?
+        incident.metadata = (incident.metadata || {}).merge(finding[:metadata] || {})
+        incident.severity = finding[:severity] if finding[:severity].present?
+        incident.status = "open" if incident.status == "acknowledged"
+      else
+        now = Time.current
+        incident = Ops::Incident.new(
+          kind: finding[:kind],
+          severity: finding[:severity],
+          status: "open",
+          title: finding[:title],
+          message: finding[:message],
+          metadata: finding[:metadata] || {},
+          fingerprint: fingerprint,
+          occurrence_count: 1,
+          first_seen_at: now,
+          last_seen_at: now
+        )
+      end
+
+      incident.save!
+      maybe_notify!(incident)
+      incident
+    end
+
+    def resolve(fingerprint:)
+      Ops::Incident.open.where(fingerprint: fingerprint).find_each(&:resolve!)
+    end
+
+    private
+
+    def fingerprint_for(finding)
+      Digest::SHA256.hexdigest([finding[:kind], finding[:title]].join("|"))
+    end
+
+    def maybe_notify!(incident)
+      return if incident.muted?
+      return unless Ops::Notifier.notify_severity?(incident.severity)
+      return if incident.notified_at.present? && incident.notified_at > COOLDOWN.call.ago
+
+      Ops::Notifier.new.notify(incident)
+      incident.update_column(:notified_at, Time.current)
+    end
+  end
+end