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/docker_container_stop.sh

@@ -2,37 +2,116 @@
 # ==============================================================================================
 # ============================= Docker Container Stop ==========================================
 # ==============================================================================================
-# Stops all running Docker containers one at a time, verifying each is stopped before
-# moving to the next. Called by array_stopping.sh as part of a planned shutdown sequence.
 #
-# ── STOP SEQUENCE PER CONTAINER ──────────────────────────────────────────────────────────────
-#   1. docker stop -t 30 (SIGTERM + 30s grace period — docker sends SIGKILL if needed)
-#   2. Verify stopped — if still running, retry up to RETRY_COUNT times
-#   3. docker kill (SIGKILL) if all retries exhausted
-#   4. Final verify — error if still running after force-kill
-#   Never moves to the next container until the current one is confirmed stopped.
+# PURPOSE
+# ─────────────────────────────────────────────────────────────────────────────
+# Gracefully stops all running Docker containers in a verified sequential order.
 #
-# ── WHY SEQUENTIAL ────────────────────────────────────────────────────────────────────────────
-# Containers may have dependencies — stopping one at a time avoids abruptly severing a
-# service while its dependents are still running and trying to use it.
+# Called by array_stopping.sh during planned shutdowns, maintenance windows,
+# and controlled reboot operations.
 #
-# ── SAFEGUARDS ────────────────────────────────────────────────────────────────────────────────
-#   Root check           — docker requires root
-#   Per-container verify — confirmed stopped before proceeding to next
-#   Retry loop           — RETRY_COUNT attempts before escalating to force-kill
-#   SIGTERM → SIGKILL    — graceful then forced, never skips graceful
-#   DOCKER_TIMEOUT       — all docker calls protected against hung daemon
-#   notify on failures   — alert if any container cannot be stopped
+# The script guarantees each container is fully stopped before moving to the
+# next one — preventing dependency breakage, partial shutdown states, and
+# abrupt service termination cascades.
 #
-# ── CONFIGURATION (master.conf) ───────────────────────────────────────────────────────────────
-#   RETRY_COUNT — retry attempts before force-kill (default 3)
-#   SLEEP       — seconds between retries
+# ==============================================================================================
+# OPERATIONAL MODEL
+# ==============================================================================================
+#
+# Shutdown is processed one container at a time:
+#
+#   1. docker stop -t 30
+#        → sends SIGTERM with graceful shutdown window
+#
+#   2. Verify container state
+#        → confirm container fully stopped before continuing
+#
+#   3. Retry if still running
+#        → up to RETRY_COUNT attempts
+#
+#   4. Escalate to docker kill
+#        → SIGKILL only after graceful attempts exhausted
+#
+#   5. Final verification
+#        → failure notification if container survives SIGKILL
+#
+# The script NEVER advances to the next container until the current one
+# is confirmed stopped or declared failed.
+#
+# ==============================================================================================
+# DESIGN PRINCIPLES
+# ==============================================================================================
+#
+# Sequential Shutdown
+#   Containers may depend on upstream services still being available during
+#   shutdown. Sequential processing reduces dependency severance during stop.
+#
+# Graceful First, Forced Last
+#   SIGTERM is always attempted before SIGKILL. The script never force-kills
+#   first unless Docker itself escalates internally after timeout expiration.
+#
+# Verification Over Assumption
+#   Docker command success alone is not trusted. Container state is verified
+#   after every stop attempt.
+#
+# Fail Loudly
+#   Containers that cannot be stopped generate notifications and non-zero exit
+#   status so orchestrators know shutdown integrity was compromised.
+#
+# ==============================================================================================
+# OPERATIONAL SAFEGUARDS
+# ==============================================================================================
+#
+# Root Enforcement
+#   Docker operations require root privileges.
+#
+# Docker Presence Check
+#   Verifies docker binary exists before execution.
+#
+# Timeout Protection
+#   All docker commands wrapped in timeout protection to prevent daemon hangs
+#   from stalling shutdown indefinitely.
+#
+# Retry Escalation
+#   Graceful retries occur before SIGKILL escalation.
+#
+# Per-Container Validation
+#   Every container state verified before progressing to the next.
+#
+# Deterministic Ordering
+#   Running container list sorted before processing for stable execution order.
+#
+# Failure Notification
+#   Containers surviving SIGKILL trigger operator notification.
+#
+# ==============================================================================================
+# CONFIGURATION
+# ==============================================================================================
+#
+# master.conf
+#
+#   RETRY_COUNT
+#       Graceful retry attempts before force-kill escalation
+#
+#   SLEEP
+#       Delay in seconds between retry attempts
+#
+# ==============================================================================================
+# RUNTIME MODES
+# ==============================================================================================
+#
+# docker_container_stop.sh
+#     Stop all running containers in verified sequential order
+#
+# docker_container_stop.sh --dry-run
+#     Preview shutdown actions without stopping containers
+#
+# docker_container_stop.sh --status
+#     Show currently running containers and configuration state
+#
+# docker_container_stop.sh --log
+#     Verbose per-container execution logging
 #
-# ── USAGE ─────────────────────────────────────────────────────────────────────────────────────
-#   docker_container_stop.sh              — stop all running containers
-#   docker_container_stop.sh --dry-run    — show which containers would be stopped
-#   docker_container_stop.sh --status     — show running containers and exit
-#   docker_container_stop.sh --log        — verbose output
 # ==============================================================================================
 
 SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"