feat: refine live outage dashboard layout

tests/test_main.sh

@@ -162,6 +162,13 @@ if [[ "$OUTPUT" == *$'\033['* ]]; then
   printf 'FAIL: NO_COLOR output contains ANSI escapes\n' >&2
   exit 1
 fi
+WIDE_OUTPUT="$(NO_COLOR=1 COLUMNS=180 render_dashboard "$NOW_EPOCH")"
+WIDE_TOP_LINE="${WIDE_OUTPUT%%$'\n'*}"
+assert_equal "180" "${#WIDE_TOP_LINE}" \
+  "the countdown divider should span the full terminal width"
+WIDE_BOTTOM_LINE="${WIDE_OUTPUT##*$'\n'}"
+assert_equal "180" "${#WIDE_BOTTOM_LINE}" \
+  "the dashboard bottom divider should span the full terminal width"
 
 FUTURE_NOW="$(TZ=Asia/Tehran date -d '2026-07-18 15:00:00' +%s)"
 build_schedule "$FIXTURE" "$FUTURE_NOW"