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/spec/services/ops/log_scanner_spec.rb

@@ -0,0 +1,9 @@
+require "rails_helper"
+
+RSpec.describe Ops::LogScanner do
+  it "crea incidenti dai pattern trovati" do
+    log = Rails.root.join("spec/fixtures/ops/sample.log").read
+
+    expect { described_class.new.ingest(log) }.to change(Ops::Incident, :count).by_at_least(2)
+  end
+end