Standardize orchestrator child-script execution and logging

Every orchestrator invoked its children differently — four near-duplicate
run_job() copies, a differently-shaped run_watchdog(), or plain inline bash
calls, each with its own take on path resolution, pass/fail naming, and
dry-run threading. Extracted one shared run_orch_child() into common.sh so
there's a single place to fix or extend this behavior going forward.

Along the way: watchdog_orchestrator.sh and monthly_maintenance.sh were
checking $VERBOSE, a variable nothing in the codebase ever assigns, so --log
silently did nothing beyond basic logging on those two. Fixed to
$ENABLE_LOGGING. watchdog_orchestrator.sh and array_started.sh had no
trailing exit, so their exit codes reflected whatever the last command
happened to return rather than actual success/failure. transcode_management.sh
had no failure notification and no summary at all. Also made
transcode_management.sh's two-script pipeline config-driven
(TRANSCODE_MANAGEMENT_SCRIPTS in master.conf) instead of hardcoded, for room
to extend it later without editing the orchestrator itself.

Orchestrators/monthly_maintenance.sh

@@ -234,8 +234,8 @@ echo "$ICON_GEAR  Scripts: ${#MONTHLY_MAINTENANCE_SCRIPTS[@]}"
 echo ""
 
 START=$(date +%s)
-PASSED=()
-FAILED=()
+JOB_PASS=()
+JOB_FAIL=()
 STEP=0
 
 # ==============================================================================================
@@ -246,47 +246,11 @@ for entry in "${MONTHLY_MAINTENANCE_SCRIPTS[@]}"; do
     (( STEP++ ))
 
     read -r -a parts <<< "$entry"
-    script_path="$ECOSYSTEM_ROOT/${parts[0]}"
     script_name=$(basename "${parts[0]}")
     extra_args=("${parts[@]:1}")
 
     echo "━━━ $ICON_GEAR Step $STEP: $script_name${extra_args:+ ${extra_args[*]}} ━━━"
-
-    if [[ ! -f "$script_path" ]]; then
-        error "$script_name — not found at $script_path"
-        FAILED+=("$script_name")
-        echo ""
-        continue
-    fi
-
-    if [[ ! -x "$script_path" ]]; then
-        warn "$script_name — not executable, fixing..."
-        chmod +x "$script_path" || {
-            error "$script_name — chmod +x failed"
-            FAILED+=("$script_name")
-            echo ""
-            continue
-        }
-    fi
-
-    if [[ "$DRY_RUN" == true ]]; then
-        warn "DRY RUN — would run: $script_name${extra_args:+ ${extra_args[*]}}"
-        PASSED+=("$script_name")
-        echo ""
-        continue
-    fi
-
-    local_args=()
-    [[ "$VERBOSE" == true ]] && local_args+=("--log")
-
-    if bash "$script_path" "${extra_args[@]}" "${local_args[@]}"; then
-        echo "$script_name — done ✅"
-        PASSED+=("$script_name")
-    else
-        warn "$script_name — failed (exit $?) — continuing to next step"
-        FAILED+=("$script_name")
-    fi
-
+    run_orch_child "$entry"
     echo ""
 done
 
@@ -307,22 +271,22 @@ fi
 echo "━━━━━ $ICON_SUMMARY MONTHLY MAINTENANCE SUMMARY ━━━━━"
 echo "$ICON_HOST    Identity: $MY_ID ($LOCAL_SERVER_NAME)"
 echo "$ICON_TIME    Duration: $(format_duration $(( END - START )))"
-[[ ${#PASSED[@]} -gt 0 ]] && echo "$ICON_DONE    Passed:   ${PASSED[*]}"
-[[ ${#FAILED[@]} -gt 0 ]] && echo "$ICON_ERROR   Failed:   ${FAILED[*]}"
+[[ ${#JOB_PASS[@]} -gt 0 ]] && echo "$ICON_DONE    Passed:   ${JOB_PASS[*]}"
+[[ ${#JOB_FAIL[@]} -gt 0 ]] && echo "$ICON_ERROR   Failed:   ${JOB_FAIL[*]}"
 echo ""
 
 if [[ "$DRY_RUN" == true ]]; then
     warn "DRY RUN — no changes made"
-elif [[ ${#FAILED[@]} -eq 0 ]]; then
+elif [[ ${#JOB_FAIL[@]} -eq 0 ]]; then
     echo "$ICON_DONE Status: all $STEP step(s) complete ✅"
     notify "Monthly maintenance complete on $(hostname) ($MY_ID) — $STEP step(s) done" \
         "Monthly Maintenance" "normal"
 else
-    warn "Status: ${#FAILED[@]} step(s) failed — ${FAILED[*]}"
-    notify "Monthly maintenance on $(hostname) ($MY_ID) — ${#FAILED[@]} step(s) failed: ${FAILED[*]}" \
+    warn "Status: ${#JOB_FAIL[@]} step(s) failed — ${JOB_FAIL[*]}"
+    notify "Monthly maintenance on $(hostname) ($MY_ID) — ${#JOB_FAIL[@]} step(s) failed: ${JOB_FAIL[*]}" \
         "Monthly Maintenance" "warning"
 fi
 echo "━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━"
 
-[[ ${#FAILED[@]} -gt 0 ]] && exit 1
+[[ ${#JOB_FAIL[@]} -gt 0 ]] && exit 1
 exit 0