Storage-mode awareness pass + doc update for System_Essentials through Partnership

All state/data file paths in scripts and PHP now resolve via STATE_DIR / DATA_DIR /
PERSISTENT_CONF_CACHE instead of hardcoded /boot/config/ or /tmp/ paths, so the
ecosystem works in both internal and appdata storage modes.

PHP layer (watchdog.php, partnership.php, fallback.php, monitor.php, snapshot.php,
config.php): all state reads switched to STATE_DIR constant; remote state reads use
the new vv_remote_state_cmd() helper which resolves the remote's SCRIPTS_DIR via
their varaverk.cfg before building the path.

conf_sync.sh: fixed SCRIPTS_ROOT → SCRIPTS_DIR bug on MY_CONF path; added
_remote_scripts_dir() to resolve partner's SCRIPTS_DIR before SCP pull.

fallback.php page: added controls card (PARTNERSHIP_ENABLED, FALLBACK_ENABLED,
FALLBACK_RSYNC_ENABLED toggles), status grid, and settings card.

README and Manual updated for System_Essentials, Watchdogs, Fallback, Rsync,
Media, Monitors, Orchestrators, Partnership: added new scripts (conf_sync,
conf_cache_save/restore, conf_cache_watchdog, play_state_sync, start_webhook_listener,
upgrade_webhook_handler), corrected all stale /boot/config/ state file paths to
$STATE_DIR/$DATA_DIR, noted webgui/php_fpm/mover/user_scripts scripts moved to
Plugin/unraid/System_Essentials, fixed start_webhook_listener.sh header (Node.js,
not PHP -S).

Media/README-Media.md

@@ -4,8 +4,9 @@ Library health, consistency, sync, and behavior-driven discovery for a multi-ser
 stack. Correct permissions so arrs can manage files. Junk removal so orphan detection
 isn't confused by scene debris. Library sync so every node tracks the same content.
 Orphan cleanup against live arr APIs so deleted content actually leaves disk. Emby
-notified automatically after every deletion. Weekly discovery adds new music, movies,
-and TV shows based on what you actually play — no manual browsing required.
+notified automatically after every deletion. Watch state synced across Emby/Jellyfin
+every 30 minutes. Quality upgrades propagate to all nodes immediately via webhook.
+Weekly discovery adds new music, movies, and TV shows based on what you actually play.
 
 > **These scripts permanently delete files.** The arr cleanup scripts are protected by
 > multiple safety layers that must all pass before anything is touched — but dry runs and
@@ -91,6 +92,19 @@ free overnight recovery.
 `lidarr_missing_art.sh` — fetch missing album and artist artwork from fanart.tv and
 fallback sources. Never overwrites existing files.
 
+**Play State Sync**  
+`play_state_sync.sh` — syncs watched/played state and resume positions across all
+configured Emby and Jellyfin servers. Newest timestamp wins. Runs every 30 minutes
+via critical_sync_maintenance.sh.
+
+**Upgrade Propagation**  
+`start_webhook_listener.sh` — Node.js HTTP server that receives Sonarr/Radarr/Lidarr
+OnUpgrade webhooks. Continuous; started at array start. Writes to
+`/var/log/varaverk/upgrade_webhook.log`.  
+`upgrade_webhook_handler.sh` — triggered by the webhook listener. Pushes the upgraded
+item folder to every remote node immediately, then triggers an arr library rescan on
+each remote so the upgraded file is accepted without triggering a redundant quality search.
+
 **Discovery**  
 `playback_aware_lidarr_discovery.sh` — behavior-driven music discovery. Scores your
 Emby play history, runs Last.fm getSimilar on top artists, adds the best matches to
@@ -138,6 +152,24 @@ playback_aware_radarr_discovery.sh   — score watch history → TMDB recommenda
 playback_aware_sonarr_discovery.sh   — score episode history → TMDB TV recommendations → add to Sonarr
 ```
 
+**Every 30 min via `critical_sync_maintenance.sh` (CRITICAL_MAINTENANCE_SCRIPTS):**
+
+```
+play_state_sync.sh          — sync watched/resume state across Emby + Jellyfin
+```
+
+**Continuous (started by `array_started.sh`):**
+
+```
+start_webhook_listener.sh   — Node.js webhook server; dispatch upgrade_webhook_handler.sh
+```
+
+**On every arr upgrade (triggered by webhook):**
+
+```
+upgrade_webhook_handler.sh  — push upgraded folder to all remote nodes + trigger arr rescan
+```
+
 **Ad-hoc or separate schedule:**
 
 ```
@@ -189,6 +221,9 @@ in `HOST*_MEDIA_PERMISSION_SHARES` and `HOST*_MEDIA_CLEAN_FOLDERS` in host*.conf
 | `lidarr_missing_art.sh` | Fetch missing album and artist artwork | Ad-hoc or separate schedule |
 | `radarr_tmdb_removed.sh` | Remove movies dropped from TMDb | Ad-hoc or weekly |
 | `sonarr_tvdb_removed.sh` | Remove series dropped from TVDB | Ad-hoc or weekly |
+| `play_state_sync.sh` | Sync watched/played state + resume positions across Emby + Jellyfin | Every 30 min via `critical_sync_maintenance.sh` |
+| `start_webhook_listener.sh` | Node.js webhook server — receive arr OnUpgrade and dispatch handler | Continuous (started by `array_started.sh`) |
+| `upgrade_webhook_handler.sh` | Push upgraded item folder to remote nodes + trigger arr rescan | On each arr upgrade (via webhook) |
 | `playback_aware_lidarr_discovery.sh` | Behavior-driven music discovery — Emby plays → Last.fm similar → Lidarr | Weekly via `weekly_sync_maintenance.sh` |
 | `playback_aware_radarr_discovery.sh` | Behavior-driven movie discovery — Emby watches → TMDB recommendations → Radarr | Weekly via `weekly_sync_maintenance.sh` |
 | `playback_aware_sonarr_discovery.sh` | Behavior-driven TV discovery — Emby episodes → TMDB TV recommendations → Sonarr | Weekly via `weekly_sync_maintenance.sh` |
@@ -228,6 +263,17 @@ Weekly discovery (WEEKLY_MAINTENANCE_SCRIPTS):
         │
         └── each discovery script fires arr search immediately after successful add
 
+Every 30 min (critical_sync_maintenance.sh CRITICAL_MAINTENANCE_SCRIPTS):
+  play_state_sync.sh ─── newest timestamp wins → watched/resume state synced
+                          across all configured Emby + Jellyfin servers
+
+Continuous (started by array_started.sh):
+  start_webhook_listener.sh ── Node.js HTTP server listens on WEBHOOK_PORT
+        │ arr OnUpgrade fires webhook → POST to http://HOST_LAN_IP:WEBHOOK_PORT/webhook?key=SECRET
+        └── upgrade_webhook_handler.sh
+              ├── rsync upgraded folder → all remote nodes immediately
+              └── trigger arr library rescan on each remote (accept new file, no quality search)
+
 Ad-hoc enrichment:
   lidarr_missing_art.sh ─────── discovers missing artwork → fetches from fanart.tv
   radarr_tmdb_removed.sh ────── status="deleted" → remove from Radarr + add exclusion