v2 post-migration bug fixes, lidarr_missing_art port, and Partnership SSH/FolderView3 enhancements

Bug fixes across the ecosystem after v1→v2 architecture migration and Unraid 7.2.5 upgrade:

- common.sh: fix _alias_array() phantom empty element (removed [@]:-} pattern), fix
  resolve_remote_ip() with Tailscale FQDN lowercase + awk fallback, add FANART/LASTFM
  key aliases in detect_hosts(), global [@]:-} sweep across 10+ scripts
- webgui_restart.sh: fix emhttp detection (pgrep emhttpd) and restart command for 7.2.5
  (/usr/local/sbin/emhttp stop && start — rc.emhttp removed in 7.2.5)
- bandwidth_monitor.sh, continuous_scripts_status.sh: fix 'local' keyword outside function
- backup_verify.sh: fix resolve_remote_ip() called before detect_hosts()
- Orchestrators: fix script display duplication bug in status output (${entry##*/})
- rsync_stop.sh, git_pull_execute.sh, partnership_manager.sh, coffee_report: lowercase all
  tailscale ip -4 call sites to match Tailscale's lowercase device names
- master_host1.conf: fix SSH key path (gmer4lfe_rsync_automation), add FANART/LASTFM keys
- master_host2.conf: add FANART/LASTFM API keys

New: Media/lidarr_missing_art.sh
- Full ecosystem port of standalone Lidarr artwork fetcher
- Fetches missing album art via fanart.tv + Last.fm APIs
- @tsv batch extraction: 1 jq call per API response vs N*albums (8050 albums in 24s)
- HOST guard (HOST1 only), --status, --dry-run, acquire_lock

New: Initial_run/ssh_setup.sh
- Generates {hostname}_rsync_automation ed25519 keypair (skip if exists, --force to regen)
- ssh-copy-id to remote via Tailscale IP, auto-updates master_host*.conf
- --validate mode: strike tracking (SSH_MAX_STRIKES, SSH_STRIKE_RESET_HRS),
  notify at limit — Tailscale-unreachable remote does NOT count as SSH strike

New: Initial_run/partnership_onboard.sh
- Orchestrator: ssh_setup.sh then partnership_manager.sh --onboard in one command

Partnership/partnership_manager.sh: FolderView3 integration
- Derive partner folder name at runtime (strip unraid- prefix case-insensitively)
- --onboard: create {Mirror}-Failover folder with failover tier containers
- --offboard (both paths): stop + rm containers in folder, remove JSON entry
- --check: calls ssh_setup.sh --validate when IP resolves but SSH state empty
- --status: shows FolderView3 folder state and containers inline

master.conf: SSH_MAX_STRIKES, SSH_STRIKE_RESET_HRS, PARTNERSHIP_FOLDERVIEW3,
PARTNERSHIP_FOLDERVIEW3_URL added to Partnership section

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

master_host1.conf

@@ -72,7 +72,7 @@
 
 # SSH key used for all server-to-server operations — rsync, failover container commands.
 # Must be in /root/.ssh/ and authorised in HOST2's /root/.ssh/authorized_keys.
-    HOST1_SSH_KEY="root/.ssh/gmer4lfe_rsync_automation"
+    HOST1_SSH_KEY="/root/.ssh/gmer4lfe_rsync_automation"
 
 # ━━━ Emby ━━━
 # Referenced by transcode_manager.sh, emby_session_report.sh, emby_database_repair.sh,
@@ -495,6 +495,8 @@
     HOST1_LIDARR_URL="http://localhost:8686"
     HOST1_LIDARR_API_KEY="b2977e71ef074bc0a0529d9fcce3b2dc"
     HOST1_LIDARR_MUSIC_ROOT="/mnt/user/Music-New"
+    HOST1_FANART_API_KEY="Yd7147a43b692df0b364b94dc47efb81"
+    HOST1_LASTFM_API_KEY="be6dc169c33ae263e690c30d18b7491d"
 
     declare -A HOST1_LIDARR_PATH_MAP=(
         ["/ext-music"]="/mnt/user/Music-New"