refactor(doorbell-touch): add build harness with monitor agent and board-specific setup

boards/esp32-s3-lcd-43/install.sh

@@ -0,0 +1,31 @@
+#!/usr/bin/env bash
+# Install LovyanGFX for esp32-s3-lcd-43
+set -euo pipefail
+
+DIR="$(cd "$(dirname "$0")" && pwd)"
+VENDOR_DIR="$DIR/../../vendor/esp32-s3-lcd-43"
+LOVGFX_DIR="$VENDOR_DIR/LovyanGFX"
+
+if [ ! -d "$LOVGFX_DIR" ]; then
+    echo "Cloning LovyanGFX..."
+    git clone --depth 1 \
+        https://github.com/lovyan03/LovyanGFX.git \
+        "$LOVGFX_DIR"
+fi
+
+# Create library.properties
+cat > "$LOVGFX_DIR/library.properties" << 'EOF'
+name=LovyanGFX
+version=1.2.0
+author=lovyan03
+maintainer=lovyan03
+sentence=Display and touch driver library for ESP32
+paragraph=Universal graphics library for ESP32 with support for various displays and touch controllers
+category=Display
+url=https://github.com/lovyan03/LovyanGFX
+architectures=esp32
+includes=LovyanGFX.hpp
+EOF
+
+mkdir -p "$LOVGFX_DIR/src"
+echo "[OK] LovyanGFX vendored for esp32-s3-lcd-43"