feat(home): import doris dashboard from workspace repo

Migrates workspace-only dashboard work from commits 6f0c5cd, c851073, and d04eff3 into the canonical truenas-stacks repo.

home/doris-dashboard/bin/cron_generate_dashboard.sh

@@ -0,0 +1,6 @@
+#!/usr/bin/env bash
+set -euo pipefail
+cd "$(dirname "$0")/.."
+hour="$(TZ=America/Chicago date +%H)"
+if (( 10#$hour < 6 || 10#$hour > 23 )); then exit 0; fi
+bin/generate_dashboard.py