Upload signed documents to paperless-ngx when all parties complete signing. Triggered automatically after audit trail generation in the submission completion flow. Features: - Uploads combined PDF (or individual results) + audit trail - Title format: 'Template Name - Signer 1, Signer 2' - ENV-based config (PAPERLESS_NGX_URL, PAPERLESS_NGX_TOKEN) - Feature inactive unless both vars are set - Background job with exponential retry (max 10 attempts) - Dedicated 'integrations' Sidekiq queue Files: - lib/submissions/upload_to_paperless.rb — Faraday multipart upload - app/jobs/upload_to_paperless_job.rb — Sidekiq job with retry - app/jobs/process_submitter_completion_job.rb — hook (2 lines) - config/sidekiq.yml — new queue - docker-compose.e2e.yml — paperless-ngx for integration tests - spec/ — unit tests (18 examples) + E2E tests (3 examples) Co-authored-by: Sebastian Noe <sebastian.schneider@boxine.de>