divoom: add pi deploy artifact manifests

Add source-controlled Puppet/Hiera contracts for edge2 Divoom-as-DM-device without replacing the live flowercore-divoom systemd deployment.

Add Divoom TV Pi HDMI systemd/Puppet deployment artifacts, LF shell-script guardrails, and focused lint coverage for the additive non-K8s deploy shape.

Co-Authored-By: Codex <codex@openai.com>

apps/fc-divoom-tv-pi/scripts/flowercore-divoom-tv-prelaunch.sh

@@ -0,0 +1,23 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+APP_BIN="${FC_DIVOOM_TV_BIN:-/opt/flowercore/divoom-tv/FlowerCore.Divoom.Tv}"
+STATE_DIR="${FC_DIVOOM_TV_STATE_DIR:-/var/lib/fc-divoom-tv}"
+LOG_DIR="${FC_DIVOOM_TV_LOG_DIR:-/var/log/fc-divoom-tv}"
+
+mkdir -p "${STATE_DIR}" "${LOG_DIR}"
+
+if [[ ! -x "${APP_BIN}" ]]; then
+  echo "[$(date -Is)] missing executable ${APP_BIN}" >&2
+  exit 1
+fi
+
+if [[ -d /sys/class/drm ]] && ! find /sys/class/drm -maxdepth 1 -name 'card*-HDMI-A-*' -print -quit | grep -q .; then
+  echo "[$(date -Is)] no HDMI connector visible yet; continuing so the app can wait for display" >&2
+fi
+
+if command -v cage >/dev/null 2>&1; then
+  echo "[$(date -Is)] cage available for fullscreen Wayland launch"
+else
+  echo "[$(date -Is)] cage not installed; direct launch fallback will be used" >&2
+fi