v1.0.0

Hardened baseline release for torrents-stack.\n\nHighlights:\n- Pinned container image tags with env overrides\n- Improved service healthchecks and startup timing tuning\n- Added CI compose validation and smoke test with health waits\n- Added Dependabot config for Actions and Docker\n- Added monthly backup/restore reminder workflow\n- Added backup/restore runbook, security policy, and issue templates\n- Added workflow badges and onboarding improvements in README