feat(@projects/@magic-civilization): ✨ add weston-headless backend support

Co-Authored-By: Lilith Autocommit <noreply@atlilith.com>

scripts/p2-72-option-b-render.sh

@@ -49,9 +49,36 @@ echo "Seed=$CP_SEED Players=$CP_PLAYERS Map=$CP_MAP_SIZE Turns=$CP_TURNS"
 echo "Output (in sandbox): $CP_OUTPUT_DIR"
 echo "Log: $LOG_FILE"
 
-# Pure-headless — no Wayland (renderer draws into the headless framebuffer,
-# Image.save_png reads from get_viewport().get_texture()).
+# Headless rendering: pure --headless uses Godot's dummy rendering server,
+# which returns null from get_viewport().get_texture() — Image.save_png
+# fails. We need a real GL context, so use weston-headless as a Wayland
+# host for the flatpak sandbox. Mirrors tools/autoplay-batch.sh --weston.
+if ! command -v weston >/dev/null 2>&1; then
+    echo "ERROR: weston not installed — cannot render screenshots headlessly" >&2
+    exit 2
+fi
+WESTON_SOCKET="p2-72-option-b-$$"
+echo "Starting weston (headless backend, socket=$WESTON_SOCKET)..."
+WESTON_LOG="/tmp/p2-72-option-b-weston.log"
+weston --backend=headless --no-config --socket="$WESTON_SOCKET" \
+    --width=1920 --height=1080 \
+    >"$WESTON_LOG" 2>&1 &
+WESTON_PID=$!
+sleep 1.5
+if ! kill -0 "$WESTON_PID" 2>/dev/null; then
+    echo "ERROR: weston failed to launch — see $WESTON_LOG" >&2
+    tail -20 "$WESTON_LOG" >&2
+    exit 3
+fi
+trap 'kill $WESTON_PID 2>/dev/null; wait $WESTON_PID 2>/dev/null' EXIT
+
+XDG_RUNTIME_DIR="${XDG_RUNTIME_DIR:-/run/user/$(id -u)}" \
 timeout "$CP_TIMEOUT_SEC" flatpak run --user \
+    --filesystem=home \
+    --socket=wayland \
+    --unset-env=DISPLAY \
+    --env=WAYLAND_DISPLAY="$WESTON_SOCKET" \
+    --filesystem=xdg-run/${WESTON_SOCKET} \
     --env=CP_SEED="$CP_SEED" \
     --env=CP_PLAYERS="$CP_PLAYERS" \
     --env=CP_CLAUDE_SLOT="$CP_CLAUDE_SLOT" \
@@ -63,7 +90,7 @@ timeout "$CP_TIMEOUT_SEC" flatpak run --user \
     --env=MC_USE_PROCEDURAL_SPRITES="1" \
     org.godotengine.Godot \
     --path "$PROJECT_DIR/src/game" \
-    --headless \
+    --display-driver wayland \
     --rendering-driver opengl3 \
     --rendering-method gl_compatibility \
     res://engine/scenes/tests/claude_vs_ai_render_proof.tscn \