[BOUNTY $150] Backup & DR Stack — Duplicati + Restic REST Server (completes #12)

[asdas6wdqc]

Summary

Implements the Backup & Disaster Recovery Stack (Issue #12, $150 USDT) with a 3-2-1 backup strategy using Duplicati and Restic REST Server.

Changes

Services Added

Service	Image	URL	Purpose
Duplicati	lscr.io/linuxserver/duplicati:2.0.11	backup.${DOMAIN}	Encrypted cloud/local backup with deduplication
Restic REST Server	restic/rest-server:0.13.0	restic.${DOMAIN}	Self-hosted backup repository for restic client

New Files

File	Purpose
stacks/backup/docker-compose.yml	Duplicati + Restic REST Server compose
stacks/backup/README.md	Complete backup guide with 3-2-1 strategy, Duplicati setup, Restic usage

3-2-1 Backup Strategy Implemented

Data → Docker volumes → Restic REST Server → MinIO (offsite)
                      → Duplicati → Cloud/MinIO

Test Plan

• docker compose up -d starts both services
• Duplicati accessible at https://backup.${DOMAIN}
• Restic REST Server accessible at https://restic.${DOMAIN}
• Can initialize restic repo via restic client
• scripts/backup.sh --list shows available stacks

Bounty

Fixes #12