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_daily_restart.sh

@@ -2,52 +2,102 @@
 # ==============================================================================================
 # ================================= Docker Daily Restart =======================================
 # ==============================================================================================
-# Restarts or starts all containers in HOST*_DAILY_RESTART_CONTAINERS.
-# Called by daily_sync_maintenance.sh via DAILY_MAINTENANCE_SCRIPTS every night at 1am.
-# Can also be run manually for ad hoc restarts.
 #
-# ── WHY DAILY RESTARTS ────────────────────────────────────────────────────────────────────────
-# Some containers degrade over time without a restart:
-#   Dispatcharr — Live TV scheduler accumulates state and slows down
-#   NginxProxyManager — connection table grows, occasional stale proxy entries
-#   Authelia — session cache benefits from periodic clearing
-# Daily restart is intentional maintenance, not just housekeeping.
+# PURPOSE
+# ─────────────────────────────────────────────────────────────────────────────
+# Restarts configured containers every night at 1am as proactive maintenance.
 #
-# ── BEHAVIOUR ─────────────────────────────────────────────────────────────────────────────────
-# Running containers → docker restart (graceful stop + start)
-# Stopped containers → left stopped — was down intentionally, do not bring back up
-# Missing containers → logged and skipped — not treated as fatal
-# Each action uses RETRY_COUNT + SLEEP from master.conf for retry logic.
+# Called by daily_sync_maintenance.sh via DAILY_MAINTENANCE_SCRIPTS. Runs inside
+# the daily maintenance window — any service downtime is absorbed by a window
+# that is already happening. Also drives docker_update.sh in normal mode: the
+# same DAILY_RESTART_CONTAINERS list is used for both restarts and image pulls,
+# so there is no second list to maintain.
 #
-# The "was running → restart, was stopped → leave stopped" rule is consistent
-# across the entire ecosystem — container state is always respected.
+# ==============================================================================================
+# DESIGN PRINCIPLES
+# ==============================================================================================
 #
-# ── SAFEGUARDS ────────────────────────────────────────────────────────────────────────────────
-# Dependency ordering — containers restart in dependency-safe order using
-#   HOST*_WATCHDOG_DEPENDENCIES from master_host*.conf. If Authelia depends on
-#   Mariadb + Redis, those restart first with CONTAINER_DELAY before Authelia starts.
+# Proactive Maintenance
+#   Daily restarts target containers known to degrade over time without
+#   crossing a clear failure threshold — connection table growth, scheduler
+#   state accumulation, session cache bloat. The watchdog cannot detect this
+#   class of degradation. Scheduled restarts clear it before it becomes visible.
 #
-# Restart verification — after each restart, container state is checked after a short
-#   settle period. If the container fails to stay running it is marked as failed and
-#   a notification is sent rather than silently passing.
+# State Respect
+#   Running containers are restarted. Stopped containers are left stopped — they
+#   were intentionally halted and this script has no authority to override that
+#   decision. This rule is consistent across the entire ecosystem.
 #
-# Timeout protection — all docker commands are wrapped in a 30 second timeout.
-#   A hung Docker daemon cannot cause this script to hang indefinitely.
-#   Timed-out commands are retried per RETRY_COUNT before marking as failed.
+# Dependency-Safe Ordering
+#   Restarts follow the same dependency ordering used by docker_watchdog.sh.
+#   Services that other containers depend on restart first. A dependent is never
+#   restarted while its dependency is still coming up.
 #
-# ── CONFIGURATION (master_host*.conf) ─────────────────────────────────────────────────────────
-#   HOST*_DAILY_RESTART_CONTAINERS — list of containers to restart daily
-#   Set by detect_hosts() alias → DAILY_RESTART_CONTAINERS used by this script
+# ==============================================================================================
+# OPERATIONAL SAFEGUARDS
+# ==============================================================================================
 #
-# ── CONFIGURATION (master.conf) ───────────────────────────────────────────────────────────────
-#   RETRY_COUNT  — retry attempts before giving up on a container
-#   SLEEP        — seconds between retry attempts
+# Dependency Ordering
+#   Containers restart in dependency-safe order using HOST*_WATCHDOG_DEPENDENCIES.
+#   CONTAINER_DELAY seconds between dependency restart and dependent restart gives
+#   the dependency time to fully initialise before dependents try to connect.
+#
+# Restart Verification
+#   After each restart, container state is checked after a settle period. A
+#   container that starts and immediately crashes is marked failed and a
+#   notification is sent — the script does not silently pass a restart that
+#   did not stick.
+#
+# Timeout Protection
+#   All docker commands wrapped in a 30 second timeout. A hung Docker daemon
+#   cannot cause this script to hang indefinitely. Timed-out commands retry
+#   per RETRY_COUNT before marking as failed.
+#
+# Lock Acquisition
+#   acquire_lock() prevents concurrent execution if a previous run is still active.
+#
+# ==============================================================================================
+# CONFIGURATION
+# ==============================================================================================
+#
+# master_host*.conf
+#
+#   HOST*_DAILY_RESTART_CONTAINERS
+#       Containers restarted nightly. Also used by docker_update.sh normal mode
+#       for image pulls — add a container once, it gets both. Aliased by
+#       detect_hosts() → DAILY_RESTART_CONTAINERS
+#
+#   HOST*_WATCHDOG_DEPENDENCIES
+#       Dependency ordering shared with docker_watchdog.sh. Aliased by
+#       detect_hosts() → WATCHDOG_DEPENDENCIES
+#
+# master.conf
+#
+#   RETRY_COUNT
+#       Retry attempts before giving up on a container
+#
+#   SLEEP
+#       Seconds between retry attempts
+#
+#   CONTAINER_DELAY
+#       Seconds to wait after restarting a dependency before starting its dependents
+#
+# ==============================================================================================
+# RUNTIME MODES
+# ==============================================================================================
+#
+# docker_daily_restart.sh
+#     Restart all containers in DAILY_RESTART_CONTAINERS
+#
+# docker_daily_restart.sh --dry-run
+#     Preview which containers would be restarted and which would be skipped
+#
+# docker_daily_restart.sh --status
+#     Show configured restart list, container states, and dependency ordering
+#
+# docker_daily_restart.sh --log
+#     Verbose per-container execution output
 #
-# ── USAGE ─────────────────────────────────────────────────────────────────────────────────────
-#   docker_daily_restart.sh              — normal restart
-#   docker_daily_restart.sh --dry-run    — preview without restarting
-#   docker_daily_restart.sh --log        — verbose output
-#   docker_daily_restart.sh --status     — show config and exit
 # ==============================================================================================
 
 SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"