Watchdogs/ folder + host conf rename

Move all watchdog scripts to a dedicated Watchdogs/ folder:
  Docker_Essentials/docker_watchdog.sh   → Watchdogs/
  unRAID_Essentials/system_watchdog.sh   → Watchdogs/
  unRAID_Essentials/resource_watchdog.sh → Watchdogs/
  Orchestrators/watchdog_orchestrator.sh → Watchdogs/
  Tools/watchdog_skip_list_manager.sh    → Watchdogs/

Rename host config files:
  master_host1.conf → host1.conf
  master_host2.conf → host2.conf

Update all references across the ecosystem:
  master.conf: WATCHDOG_ORCHESTRATOR_SCRIPTS paths → Watchdogs/
  load_config.sh: host*.conf glob + all comments
  git_pull_execute.sh: sparse checkout glob + all comments
  Partnership/ssh_setup.sh: HOST_CONF path construction
  user_script_plug-in.sh: all script paths + per-host conf path
  common.sh, README.md, README-User_Script_Plug-in.md: comment refs
  All Partnership, Fallback, Monitors, Transcodes, Tools scripts: comment refs

Docker_Essentials/downloaders_reset.sh

@@ -83,7 +83,7 @@
 # CONFIGURATION
 # ==============================================================================================
 #
-# master_host*.conf
+# host*.conf
 #
 #   HOST*_SLSKD_URL / HOST*_SLSKD_API_KEY / HOST*_SLSKD_FAILED_IMPORTS_DIR
 #       slskd connection and failed imports path. Aliased by detect_hosts()
@@ -567,7 +567,7 @@ if [[ -n "$QBIT_URL" ]] && [[ -n "$QBIT_USERNAME" ]]; then
 
     if [[ -z "$QBIT_COOKIE" ]]; then
         error "Failed to authenticate with qBittorrent — check QBIT_USERNAME/PASSWORD"
-        notify "qBittorrent auth failed on $(hostname) — check credentials in master_host*.conf" "Downloaders Reset" "warning"
+        notify "qBittorrent auth failed on $(hostname) — check credentials in host*.conf" "Downloaders Reset" "warning"
         ((TOTAL_FAIL++))
     else
         TORRENTS=$(curl -sf --max-time 15 \