feat: slskd reconnect guard in downloaders_reset, mass v2 sync

- downloaders_reset: connection check block before slskd API sections;
  triggers PUT /api/v0/server reconnect if disconnected, polls 60s,
  gates Stuck Searches and Dead Transfer Records on SLSKD_CONNECTED
- Sync all modified/new/deleted files from v2 refactor across Docker_Essentials,
  Media, Monitors, Partnership, Rsync, Tools, Transcodes, unRAID_Essentials,
  common.sh, master confs, and new Manual/README docs

Docker_Essentials/downloaders_reset.sh

@@ -176,6 +176,56 @@ fi
 [[ -n "$SABNZBD_URL" ]] && log "SABnzbd active on $MY_ID"
 [[ -n "$QBIT_URL" ]]    && log "qBittorrent active on $MY_ID"
 
+# ==============================================================================================
+# ━━━ slskd — Connection Check ━━━
+# ==============================================================================================
+# slskd's internal watchdog doesn't always recover from disconnection. Check before
+# running API-dependent sections; attempt reconnect if down.
+
+SLSKD_CONNECTED=false
+
+if [[ -n "$SLSKD_URL" ]] && [[ -n "$SLSKD_API_KEY" ]]; then
+    echo ""
+    echo "━━━ $ICON_SYNC slskd — Connection Check ━━━"
+
+    _slskd_is_connected() {
+        local state
+        state=$(curl -sf --max-time 10 \
+            -H "X-Api-Key: $SLSKD_API_KEY" \
+            "$SLSKD_URL/api/v0/application" 2>/dev/null | \
+            jq -r '.server.isConnected // false' 2>/dev/null)
+        [[ "$state" == "true" ]]
+    }
+
+    if _slskd_is_connected; then
+        log "slskd connected to Soulseek ✅"
+        SLSKD_CONNECTED=true
+    else
+        warn "slskd disconnected — triggering reconnect"
+        curl -sf --max-time 10 -X PUT \
+            -H "X-Api-Key: $SLSKD_API_KEY" \
+            -H "Content-Type: application/json" \
+            "$SLSKD_URL/api/v0/server" \
+            -d '{"address":"server.slsknet.org","port":2242}' \
+            >/dev/null 2>&1
+
+        _ELAPSED=0
+        while [[ "$_ELAPSED" -lt 60 ]]; do
+            sleep 10
+            _ELAPSED=$(( _ELAPSED + 10 ))
+            if _slskd_is_connected; then
+                log "slskd reconnected after ${_ELAPSED}s ✅"
+                SLSKD_CONNECTED=true
+                break
+            fi
+            log "  waiting... (${_ELAPSED}s / 60s)"
+        done
+
+        [[ "$SLSKD_CONNECTED" != true ]] && \
+            warn "slskd still disconnected after 60s — skipping API-dependent sections"
+    fi
+fi
+
 # ==============================================================================================
 # ━━━ slskd — Stuck Searches ━━━
 # ==============================================================================================
@@ -183,7 +233,7 @@ fi
 # Prevents 409 Conflict error on next Soularr startup when it tries to
 # create a search with the same ID that already exists in a terminal state.
 
-if [[ -n "$SLSKD_URL" ]] && [[ -n "$SLSKD_API_KEY" ]]; then
+if [[ -n "$SLSKD_URL" ]] && [[ -n "$SLSKD_API_KEY" ]] && [[ "$SLSKD_CONNECTED" == true ]]; then
     echo ""
     echo "━━━ 🔍 slskd — Stuck Searches ━━━"
 
@@ -236,7 +286,7 @@ fi
 # Prevents Soularr 404 loop when polling a user whose transfer no longer exists.
 # Safety: NEVER removes transfers that are InProgress or Queued — active downloads protected.
 
-if [[ -n "$SLSKD_URL" ]] && [[ -n "$SLSKD_API_KEY" ]]; then
+if [[ -n "$SLSKD_URL" ]] && [[ -n "$SLSKD_API_KEY" ]] && [[ "$SLSKD_CONNECTED" == true ]]; then
     echo ""
     echo "━━━ 🔍 slskd — Dead Transfer Records ━━━"